[Federal Register Volume 81, Number 250 (Thursday, December 29, 2016)]
[Rules and Regulations]
[Pages 96204-96239]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-29994]



[[Page 96203]]

Vol. 81

Thursday,

No. 250

December 29, 2016

Part II





 Department of Energy





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 10 CFR Parts 429, 430, and 431





 Energy Conservation Program for Consumer Products and Certain 
Commercial and Industrial Equipment: Test Procedures for Consumer and 
Commercial Water Heaters; Final Rule

  Federal Register / Vol. 81 , No. 250 / Thursday, December 29, 2016 / 
Rules and Regulations  

[[Page 96204]]


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DEPARTMENT OF ENERGY

10 CFR Parts 429, 430, and 431

[Docket No. EERE-2015-BT-TP-0007]
RIN 1904-AC91


Energy Conservation Program for Consumer Products and Certain 
Commercial and Industrial Equipment: Test Procedures for Consumer and 
Commercial Water Heaters

AGENCY: Office of Energy Efficiency and Renewable Energy, Department of 
Energy.

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: The U.S. Department of Energy (DOE), in this final rule, 
establishes mathematical conversion factors to translate the current 
energy conservation standards and the measured values determined under 
the energy factor, thermal efficiency, and standby loss test procedures 
for consumer water heaters and certain commercial water heaters to 
those determined under the more recently adopted uniform energy factor 
test procedure. As required by the Energy Policy and Conservation Act 
of 1975 (EPCA), as amended, DOE initially presented proposals for 
establishing a mathematical conversion factor in a notice of proposed 
rulemaking (NOPR) published on April 14, 2015 (April 2015 NOPR). Upon 
further analysis and review of the public comments received in response 
to the April 2015 NOPR, DOE published a supplemental notice of proposed 
rulemaking on August 30, 2016 (August 2016 SNOPR). These proposed 
rulemakings serve as the basis for the final rule.

DATES: The effective date of this rule is December 29, 2016. The 
conversion factors established in this rule shall apply beginning on 
December 29, 2016 through December 29, 2017.

ADDRESSES: The docket, which includes Federal Register notices, public 
meeting attendee lists and transcripts, comments, and other supporting 
documents/materials, is available for review at www.regulations.gov. 
All documents in the docket are listed in the www.regulations.gov 
index. However, not all documents listed in the index may be publicly 
available, such as those containing information that is exempt from 
public disclosure.
    A link to the docket Web page can be found at https://www.regulations.gov/docket?DRegulations.gov-Docket Folder Summary=EERE-
2015-BT-TP-0007. The docket Web page contains simple instructions on 
how to access all documents, including public comments, in the docket.

FOR FURTHER INFORMATION CONTACT: Ms. Ashley Armstrong, U.S. Department 
of Energy, Office of Energy Efficiency and Renewable Energy, Building 
Technologies Office, EE-5B, 1000 Independence Avenue SW., Washington, 
DC 20585-0121. Telephone: (202) 586-6590. Email: 
[email protected].

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Authority and Background
II. Summary of the Final Rule
III. Discussion
    A. Purpose
    B. Scope
    1. Storage Volume and Input Capacity Limitations
    2. Water Temperature Limitations
    3. Grid-Enabled Water Heaters
    4. Residential-Duty Commercial Water Heaters
    C. Approaches for Developing Conversions
    1. Analytical Methods Approach
    2. Empirical Regression Approach
    3. Hybrid Approach
    D. Testing Results and Analysis of Test Data
    1. Impact of Certain Water Heater Attributes on Efficiency 
Ratings
    2. Conversion Factor Derivation
    a. Consumer Storage Water Heaters
    b. Consumer Instantaneous Water Heaters
    c. Residential-Duty Commercial Water Heaters
    i. Gas-Fired Storage and Oil-Fired Storage
    ii. Electric Instantaneous
    d. Grid-Enabled Storage Water Heaters
    3. Energy Conservation Standard Derivation
    E. Enforcement Policy
    F. Certification
    G. Effective Date
IV. Procedural Issues and Regulatory Review
    A. Review Under Executive Order 12866
    B. Review Under the Regulatory Flexibility Act
    C. Review Under the Paperwork Reduction Act of 1995
    D. Review Under the National Environmental Policy Act of 1969
    E. Review Under Executive Order 13132
    F. Review Under Executive Order 12988
    G. Review Under the Unfunded Mandates Reform Act of 1995
    H. Review Under the Treasury and General Government 
Appropriations Act, 1999
    I. Review Under Executive Order 12630
    J. Review Under Treasury and General Government Appropriations 
Act, 2001
    K. Review Under Executive Order 13211
    L. Review Under Section 32 of the Federal Energy Administration 
Act of 1974
    M. Congressional Notification
V. Approval of the Office of the Secretary

I. Authority and Background

    Title III Part B \1\ of the Energy Policy and Conservation Act of 
1975 (``EPCA'' or, ``the Act''), Public Law 94-163 (42 U.S.C. 6291-
6309, as codified) sets forth a variety of provisions designed to 
improve energy efficiency and established the Energy Conservation 
Program for Consumer Products Other Than Automobiles.\2\ Consumer water 
heaters, one subject of this document, are a ``covered product'' under 
EPCA. (42 U.S.C. 6292(a)(4)) Title III, Part C \3\ of EPCA, Public Law 
94-163 (42 U.S.C. 6311-6317, as codified), added by Public Law 95-619, 
Title IV, Sec. 441(a), established the Energy Conservation Program for 
Certain Industrial Equipment, which includes commercial water heating 
equipment, another subject of this rulemaking, as ``covered 
equipment.'' (42 U.S.C. 6311(1)(K))
---------------------------------------------------------------------------

    \1\ For editorial reasons, upon codification in the U.S. Code, 
Part B was redesignated Part A.
    \2\ All references to EPCA in this document refer to the statute 
as amended through the Energy Efficiency Improvement Act of 2015 
(EEIA 2015), Public Law 114-11 (April 30, 2015).
    \3\ For editorial reasons, upon codification in the U.S. Code, 
Part C was redesignated Part A-1.
---------------------------------------------------------------------------

    Under EPCA, DOE's energy conservation program generally consists of 
four parts: (1) Testing; (2) labeling; (3) energy conservation 
standards; and (4) certification and enforcement procedures. The 
testing requirements consist of test procedures that manufacturers of 
covered products and equipment must use as the basis for certifying to 
DOE that their products and equipment comply with the applicable energy 
conservation standards adopted under EPCA, and for making other 
representations about the efficiency of those products. (42 U.S.C. 
6293(c); 42 U.S.C. 6295(s); 42 U.S.C. 6314) Similarly, DOE must use 
these test procedures to determine whether such products and certain 
equipment comply with any relevant standards promulgated under EPCA. 
(42 U.S.C. 6295(s); 42 U.S.C. 6314)
    EPCA contains what is known as an ``anti-backsliding'' provision, 
which prevents the Secretary from prescribing any amended standard that 
either increases the maximum allowable energy use or decreases the 
minimum required energy efficiency of a covered product. (42 U.S.C. 
6295(o)(1); 6313(a)(6)(B)(iii)(I)) Also, the Secretary may not 
prescribe an amended or new standard if interested persons have 
established by a preponderance of the evidence that the standard is 
likely to result in the unavailability in the United States of any 
covered product type (or class) of performance characteristics 
(including reliability), features, sizes, capacities, and volumes that 
are substantially the same as those generally available in the United 
States. (42 U.S.C. 6295(o)(4); 6313(a)(6)(B)(iii)(II))

[[Page 96205]]

    EPCA prescribed the energy conservation standards for consumer 
water heaters, shown in Table I.1 (42 U.S.C. 6295(e)(1)), and directed 
DOE to conduct further rulemakings to determine whether to amend these 
standards. (42 U.S.C. 6295(e)(4)(A)-(B)) DOE notes that under 42 U.S.C. 
6295(m), the agency must periodically review its already established 
energy conservation standards for a covered product. Under this 
requirement, the next review that DOE would need to conduct must occur 
no later than six years from the issuance of a final rule establishing 
or amending a standard for a covered product. DOE also notes that the 
statutory energy conservation standards apply to both storage and 
instantaneous consumer water heaters regardless of volume capacity.

Table I.1--EPCA Initial Energy Conservation Standards for Consumer Water
                                 Heaters
------------------------------------------------------------------------
             Product class                        Energy factor
------------------------------------------------------------------------
Gas Water Heater.......................  0.62-(0.0019 x Rated Storage
                                          Volume in gallons).
Oil Water Heater.......................  0.59-(0.0019 x Rated Storage
                                          Volume in gallons).
Electric Water Heater..................  0.95-(0.00132 x Rated Storage
                                          Volume in gallons).
------------------------------------------------------------------------

    The initial test procedures for water heaters were prescribed in a 
final rule published on October 4, 1977. 42 FR 54110. On October 17, 
1990, DOE published a final rule which updated the test procedure from 
a no-draw test to a six-draw, 24-hour simulated-use test. 55 FR 42162. 
The effect of this change in test procedure was investigated on a 
sample of representative units and based on the results of testing on 
those units, DOE updated the energy conservation standard for electric 
water heaters to reflect the new test procedure. To account for the 
change in test procedure for electric water heaters, DOE amended the 
standard to 0.93-(0.00132 x Rated Storage Volume). Id. at 42177.
    On April 16, 2010, DOE published a final rule (hereinafter referred 
to as the ``April 2010 final rule'') that amended the energy 
conservation standards for specified classes of consumer water heaters, 
and maintained the existing energy conservation standards for tabletop 
and electric instantaneous water heaters. 75 FR 20112. The standards 
adopted by the April 2010 final rule are shown below in Table I.2. 
These standards apply to all water heater product classes listed in 
Table I.2 and manufactured in, or imported into, the United States on 
or after April 16, 2015, for all classes except for tabletop and 
electric instantaneous. For these latter two classes, compliance with 
these standards has been required since April 15, 1991. 55 FR 42162 
(Oct. 17, 1990). Current energy conservation standards for consumer 
water heaters can be found in DOE's regulations at 10 CFR 430.32(d).

 Table I.2--DOE Energy Conservation Standards for Consumer Water Heaters
------------------------------------------------------------------------
                                     Rated storage
          Product class               volume ***       Energy factor **
------------------------------------------------------------------------
Gas-fired Storage...............  >=20 gal and <=55   0.675-(0.0015 x
                                   gal.                Vs)
                                  >55 gal and <=100   0.8012-(0.00078 x
                                   gal.                Vs)
Oil-fired Storage...............  <=50 gal..........  0.68-(0.0019 x Vs)
Electric Storage................  >=20 gal and <=55   0.960-(0.0003 x
                                   gal.                Vs)
                                  >55 gal and <=120   2.057-(0.00113 x
                                   gal.                Vs)
Tabletop *......................  >=20 gal and <=120  0.93-(0.00132 x
                                   gal.                Vs)
Gas-fired Instantaneous [dagger]  <2 gal............  0.82-(0.0019 x Vs)
Electric Instantaneous *........  <2 gal............  0.93-(0.00132 x
                                                       Vs)
------------------------------------------------------------------------
* Tabletop and electric instantaneous water heater standards were not
  updated by the April 2010 final rule.
** Vs is the ``Rated Storage Volume'' (in gallons), as determined by 10
  CFR 429.17.
*** Rated Storage Volume limitations result from either a lack of test
  procedure coverage or from divisions created by DOE when adopting
  standards. The division at 55 gallons for gas-fired and electric
  storage water heaters was established in the April 16, 2010 final rule
  amending energy conservation standards. 75 FR 20112. The other storage
  volume limitations shown in this table are a result of test procedure
  applicability and are discussed in the July 2014 final rule. 79 FR
  40542 (July 11, 2014).
[dagger] The standard for gas-fired instantaneous water heaters applies
  only to gas-fired instantaneous water heaters with a rated input of
  greater than 50,000 Btu/h.

    The initial Federal energy conservation standards and test 
procedures for commercial water heating equipment were added to EPCA as 
an amendment made by the Energy Policy Act of 1992 (EPACT). (42 U.S.C. 
6313(a)(5)) These initial energy conservation standards corresponded to 
the efficiency levels contained in the American Society of Heating, 
Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard 90.1 
(ASHRAE Standard 90.1) in effect on October 24, 1992. The statute 
provided that if the efficiency levels in ASHRAE Standard 90.1 were 
amended after October 24, 1992, the Secretary must establish an amended 
uniform national standard at new minimum levels for each equipment type 
specified in ASHRAE Standard 90.1, unless DOE determines, through a 
rulemaking supported by clear and convincing evidence, that national 
standards more stringent than the new minimum levels would result in 
significant additional energy savings and be technologically feasible 
and economically justified. (42 U.S.C. 6313(a)(6)(A)(ii)(I)-(II)) The 
statute was subsequently amended to require DOE to review its standards 
for commercial water heaters (and other ``ASHRAE equipment'') every six 
years. (42 U.S.C. 6313(a)(6)(C)) On January 12, 2001, DOE published a 
final rule for commercial water heating equipment that amended energy 
conservation standards by adopting the levels in ASHRAE Standard 90.1-
1999 for all types of commercial water heating equipment, except for 
electric storage water heaters. 66 FR 3336. For electric storage water 
heaters, the standard in ASHRAE Standard 90.1-1999 was less stringent 
than the standard prescribed in EPCA and, consequently, would have 
increased energy consumption, so DOE maintained the standards for 
electric

[[Page 96206]]

storage water heaters at the statutorily prescribed level. DOE 
published the most recent final rule for commercial water heating 
equipment standards on July 17, 2015, in which DOE adopted the thermal 
efficiency level for oil-fired storage water heaters that was included 
in ASHRAE 90.1-2013. 80 FR 42614. The current standards for commercial 
water heating equipment are presented in Table I.3.

                 Table I.3--Energy Conservation Standards for Commercial Water Heating Equipment
----------------------------------------------------------------------------------------------------------------
                                                                          Energy conservation standards *
                                                                  ----------------------------------------------
                                                                    Minimum thermal
                                                                       efficiency
          Equipment category                       Size                (equipment        Maximum standby loss
                                                                    manufactured on   (equipment manufactured on
                                                                   and after October     and after October 29,
                                                                      9, 2015) **      2003) ** [dagger][dagger]
                                                                      [dagger]  %
----------------------------------------------------------------------------------------------------------------
Electric storage water heaters........  All......................                N/A  0.30 + 27/Vm (%/h)
Gas-fired storage water heaters.......  <=155,000 Btu/h..........                 80  Q/800 + 110(Vr)\1/2\ (Btu/
                                        >155,000 Btu/h...........                 80   h)
                                                                                      Q/800 + 110(Vr)\1/2\ (Btu/
                                                                                       h)
Oil-fired storage water heaters.......  <=155,000 Btu/h..........        [dagger] 80  Q/800 + 110(Vr)\1/2\ (Btu/
                                        >155,000 Btu/h...........        [dagger] 80   h)
                                                                                      Q/800 + 110(Vr)\1/2\ (Btu/
                                                                                       h)
Electric instantaneous water heaters    <10 gal..................                 80  N/A
 [dagger][dagger][dagger].              >=10 gal.................                 77  2.30 + 67/Vm (%/h)
Gas-fired instantaneous water heaters   <10 gal..................                 80  N/A
 and hot water supply boilers.          >=10 gal.................                 80  Q/800 + 110(Vr) \1/2\ (Btu/
                                                                                       h)
Oil-fired instantaneous water heater    <10 gal..................                 80  N/A
 and hot water supply boilers.          >=10 gal.................                 78  Q/800 + 110(Vr)\1/2\ (Btu/
                                                                                       h)
                                                                  ----------------------------------------------
                                                                             Minimum thermal insulation
                                                                  ----------------------------------------------
Unfired hot water storage tank........  All......................                      R-12.5
----------------------------------------------------------------------------------------------------------------
* Vm is the measured storage volume, and Vr is the rated volume, both in gallons. Q is the nameplate input rate
  in Btu/h.
** For hot water supply boilers with a capacity of less than 10 gallons: (1) The standards are mandatory for
  units manufactured on and after October 21, 2005 and (2) units manufactured on or after October 23, 2003, but
  prior to October 21, 2005, must meet either the standards listed in this table or the applicable standards in
  Subpart E of 10 CFR 431 for a ``commercial packaged boiler.''
[dagger] For oil-fired storage water heaters: (1) The standards are mandatory for equipment manufactured on and
  after October 9, 2015, and (2) equipment manufactured prior to that date must meet a minimum thermal
  efficiency level of 78 percent.
[dagger][dagger] Water heaters and hot water supply boilers having more than 140 gallons of storage capacity
  need not meet the standby loss requirement if: (1) The tank surface area is thermally insulated to R-12.5 or
  more, (2) a standing pilot light is not used, and (3) for gas-fired or oil-fired storage water heaters, they
  have a fire damper or fan-assisted combustion.
[dagger][dagger][dagger] Energy conservation standards for electric instantaneous water heaters are included in
  EPCA. (42 U.S.C. 6313(a)(5)(D)-(E)). The compliance date for these energy conservation standards is January 1,
  1994. In a NOPR for energy conservation standards for commercial water heating equipment published on May 31,
  2016, DOE proposed to codify these standards for electric instantaneous water heaters in its regulations at 10
  CFR 431.110. 81 FR 34440.

    On December 18, 2012, the American Energy Manufacturing Technical 
Corrections Act (AEMTCA), Public Law 112-210, was signed into law. In 
relevant part, it amended EPCA to require that DOE publish a final rule 
establishing a uniform efficiency descriptor and accompanying test 
methods for consumer water heaters and certain commercial water heating 
equipment \4\ within one year of the enactment of AEMTCA. (42 U.S.C. 
6295(e)(5)(B)) AEMTCA requires that the final rule must replace the 
energy factor (EF), thermal efficiency (TE), and standby loss (SL) 
metrics with a uniform efficiency descriptor. (42 U.S.C. 6295(e)(5)(C)) 
On July 11, 2014, DOE published a final rule that fulfilled these 
requirements. 79 FR 40542 (July 2014 final rule). AEMTCA further 
requires that, beginning one year after the date of publication of 
DOE's final rule establishing the uniform descriptor (i.e., July 13, 
2015), the efficiency standards for the consumer water heaters and 
residential-duty commercial water heaters identified in the July 2014 
final rule must be denominated according to the uniform efficiency 
descriptor established in that final rule (42 U.S.C. 6295(e)(5)(D)), 
and that DOE must develop a mathematical conversion for converting the 
measurement of efficiency from the test procedures and metrics in 
effect at that time to the uniform efficiency descriptor. (42 U.S.C. 
6295(e)(5)(E)(i)-(ii))
---------------------------------------------------------------------------

    \4\ The uniform efficiency descriptor and accompanying test 
procedure apply to commercial water heating equipment with 
residential applications defined in the test procedure final rule 
published July 11, 2014, as a ``residential-duty commercial water 
heater.'' See 79 FR 40542, 40586.
---------------------------------------------------------------------------

    EPCA provides that any covered water heater (i.e., under DOE's 
rulemaking, all consumer water heaters and residential-duty commercial 
water heaters) manufactured prior to the effective date of the UEF test 
procedure final rule (i.e., July 13, 2015) that complied with the 
efficiency standards and labeling requirements applicable at the time 
of manufacture will be considered to comply with the UEF test procedure 
final rule and with any revised labeling requirements established by 
the Federal Trade Commission (FTC) to carry out the UEF test procedure 
final rule. (42 U.S.C. 6295(e)(5)(K)) DOE's interpretation and 
application of this provision are discussed in detail in section III.E.
    As noted previously, in the July 2014 final rule, DOE amended its 
test procedure for consumer and certain commercial water heaters. 79 FR 
40542. The July 2014 final rule for consumer and certain commercial 
water heaters satisfied the AEMTCA requirements to develop a uniform 
efficiency descriptor to replace the EF, TE, and SL metrics. The 
amended test procedure includes provisions for determining the uniform 
energy factor (UEF), as well as the annual energy consumption of these 
products. Furthermore, the uniform descriptor test procedure can be 
applied

[[Page 96207]]

to: (1) Consumer water heaters (including certain consumer water 
heaters that are covered products under EPCA's definition of ``water 
heater'' at 42 U.S.C. 6291(27), but that were not addressed by the 
previous test method); and (2) commercial water heaters that have 
residential applications. The major modifications to the EF test 
procedure to establish the uniform descriptor test method included the 
use of multiple draw patterns and different draw patterns, and changes 
to the set-point temperature. In addition, DOE expanded the scope of 
the test method to include all storage volumes, specifically by 
including test procedure provisions that are applicable to water 
heaters with storage volumes between 2 gallons (7.6 L) and 20 gallons 
(76 L), and to clarify applicability to electric instantaneous water 
heaters. DOE also established a new definition for ``residential-duty 
commercial water heater'' and re-categorized certain commercial water 
heaters into this class.
    The Energy Efficiency Improvement Act of 2015 (EEIA 2015) (Pub. L. 
114-11) was enacted on April 30, 2015. Among other things, EEIA 2015 
added a definition of ``grid-enabled water heater'' to EPCA's energy 
conservation standards for consumer water heaters. (42 U.S.C. 
6295(e)(6)(A)(ii)) These products are intended for use as part of an 
electric thermal storage or demand response program. One of the 
criteria in EPCA that defines a ``grid-enabled water heater'' is the 
requirement that it meet a certain energy factor (specified by a 
formula set forth in the statute), or an equivalent alternative 
standard that DOE may prescribe. Id. On August 11, 2015, DOE published 
a final rule in the Federal Register to implement the changes to EPCA 
by placing the energy conservation standards and related definitions in 
the Code of Federal Regulations (CFR). 80 FR 48004. As the energy 
conservation standard for grid-enabled water heaters is in terms of 
energy factor, DOE is addressing these products in this final rule to 
adopt a mathematical conversion to express the energy conservation 
standard in terms of UEF.
    On September 15, 2016, the Federal Trade Commission (FTC) published 
a final rule (``FTC 2016 Final Rule'') updating the EnergyGuide label 
to reflect changes to the DOE test procedure. The effective date of the 
FTC 2016 Final Rule is June 12, 2017. 81 FR 63634.
    This final rule satisfies the requirements of AEMTCA to develop a 
mathematical conversion factor for converting the EF, TE, and SL 
metrics to the UEF metric. (42 U.S.C. 6295(e)(5)(E)) DOE published a 
notice of proposed rulemaking on April 14, 2015 and a supplemental 
notice of proposed rulemaking on August 30, 2016, which included 
proposed mathematical conversion factors and the proposed energy 
conservation standards expressed in terms of the UEF metric. 80 FR 
20116 and 81 FR 59736.

II. Summary of the Final Rule

    In this final rule, DOE establishes a mathematical conversion 
factor between the values determined using the EF, TE, and SL test 
procedures (including the first-hour rating or maximum gallons per 
minute (GPM) rating, as applicable), and the values that would be 
determined using the uniform efficiency descriptor test procedure 
established in the July 2014 final rule (i.e., UEF and first-hour 
rating or maximum GPM rating).
    The mathematical conversion factor required by AEMTCA is a bridge 
between the efficiency and delivery capacity values obtained through 
testing under the EF, TE, and SL test procedures and those obtained 
under the uniform efficiency descriptor test procedure published in the 
July 2014 final rule. DOE conducted a series of tests on the classes of 
water heaters included within the scope of this rulemaking (see section 
III.B for details on the scope) and relied upon that test data and test 
data submitted by interested parties, along with the approaches 
summarized in section III.C, to calculate the conversion factors 
established in this final rule. Subsequently, DOE used the conversion 
factors to derive minimum energy conservation standards in terms of 
UEF, as shown in Table II.1 and Table II.2. The standards denominated 
in UEF are neither more nor less stringent than the EF-denominated 
standards for consumer water heaters and for commercial water-heating 
equipment based on the thermal efficiency and standby loss metrics.

               Table II.1--Consumer Water Heater Energy Conservation Standards Denominated in UEF
----------------------------------------------------------------------------------------------------------------
                                         Rated storage volume
            Product class                and input rating (if         Draw pattern        Uniform energy factor
                                             applicable)
----------------------------------------------------------------------------------------------------------------
Gas-fired Storage Water Heater.......  >=20 gal and <=55 gal..  Very Small.............  0.3456 - (0.0020 x Vr)
                                       .......................  Low....................  0.5982 - (0.0019 x Vr).
                                       .......................  Medium.................  0.6483 - (0.0017 x Vr).
                                       .......................  High...................  0.6920 - (0.0013 x Vr).
                                       >55 gal and <=100 gal..  Very Small.............  0.6470 - (0.0006 x Vr).
                                       .......................  Low....................  0.7689 - (0.0005 x Vr).
                                       .......................  Medium.................  0.7897 - (0.0004 x Vr).
                                       .......................  High...................  0.8072 - (0.0003 x Vr).
Oil-fired Storage Water Heater.......  <=50 gal...............  Very Small.............  0.2509 - (0.0012 x Vr).
                                       .......................  Low....................  0.5330 - (0.0016 x Vr).
                                       .......................  Medium.................  0.6078 - (0.0016 x Vr).
                                       .......................  High...................  0.6815 - (0.0014 x Vr).
Electric Storage Water Heaters.......  >=20 gal and <=55 gal..  Very Small.............  0.8808 - (0.0008 x Vr).
                                       .......................  Low....................  0.9254 - (0.0003 x Vr).
                                       .......................  Medium.................  0.9307 - (0.0002 x Vr).
                                       .......................  High...................  0.9349 - (0.0001 x Vr).
                                       >55 gal and <=120 gal..  Very Small.............  1.9236 - (0.0011 x Vr).
                                       .......................  Low....................  2.0440 - (0.0011 x Vr).
                                       .......................  Medium.................  2.1171 - (0.0011 x Vr).
                                       .......................  High...................  2.2418 - (0.0011 x Vr).
Tabletop Water Heater................  >=20 gal and <=120 gal.  Very Small.............  0.6323 - (0.0058 x Vr).
                                       .......................  Low....................  0.9188 - (0.0031 x Vr).
                                       .......................  Medium.................  0.9577 - (0.0023 x Vr).
                                       .......................  High...................  0.9884 - (0.0016 x Vr).

[[Page 96208]]

 
Instantaneous Gas-fired Water Heater   <2 gal and >50,000 Btu/  Very Small.............  0.80
 **.                                    h.
                                       .......................  Low....................  0.81.
                                       .......................  Medium.................  0.81.
                                       .......................  High...................  0.81.
Instantaneous Electric Water Heater    < 2 gal................  Very Small.............  0.91.
 **.
                                       .......................  Low....................  0.91.
                                       .......................  Medium.................  0.91.
                                       .......................  High...................  0.92.
Grid-Enabled Water Heater............  >75 gal................  Very Small.............  1.0136 - (0.0028 x Vr).
                                       .......................  Low....................  0.9984 - (0.0014 x Vr).
                                       .......................  Medium.................  0.9853 - (0.0010 x Vr).
                                       .......................  High...................  0.9720 - (0.0007 x Vr).
----------------------------------------------------------------------------------------------------------------
* Vr is the ``Rated Storage Volume'' (in gallons), as determined by 10 CFR 429.17.
** For instantaneous water heaters the standard is represented as a single value rather than as a function of
  storage volume. Because the UEF standard only applies to models with less than 2 gallons of storage volume,
  the coefficient becomes zero, and the standard does not vary for models between 0 and 2 gallons.


Table II.2--Residential-Duty Commercial Water Heater Energy Conservation
                      Standards Denominated in UEF
------------------------------------------------------------------------
                                                        Uniform energy
          Product class              Draw pattern           factor
------------------------------------------------------------------------
Gas-fired Storage...............  Very Small........  0.2674-(0.0009 x
                                                       Vr)
                                  Low...............  0.5362-(0.0012 x
                                                       Vr)
                                  Medium............  0.6002-(0.0011 x
                                                       Vr)
                                  High..............  0.6597-(0.0009 x
                                                       Vr)
Oil-fired Storage...............  Very Small........  0.2932-(0.0015 x
                                                       Vr)
                                  Low...............  0.5596-(0.0018 x
                                                       Vr)
                                  Medium............  0.6194-(0.0016 x
                                                       Vr)
                                  High..............  0.6740-(0.0013 x
                                                       Vr)
Electric Instantaneous **.......  Very Small........  0.80.
                                  Low...............  0.80.
                                  Medium............  0.80.
                                  High..............  0.80.
------------------------------------------------------------------------
* Vr is the ``Rated Storage Volume'' (in gallons), as determined by 10
  CFR 429.44.
** For instantaneous water heaters the standard is represented as a
  single value rather than as a function of storage volume. Because the
  UEF standard only applies to models with less than 2 gallons of
  storage volume, the coefficient becomes zero, and the standard does
  not vary for models between 0 and 2 gallons.

    The conversion factor formulas may be used for making 
representations regarding energy efficiency or energy use until 
December 29, 2017. After that, all representations regarding energy 
efficiency or energy use must be based on testing (either directly or 
through the application of an AEDM, where permitted). In addition, EPCA 
requires that a water heater be considered to comply with the July 2014 
final rule on and after July 13, 2015 (the effective date of the July 
2014 final rule) and with any revised labeling requirements established 
by the FTC to carry out the July 2014 final rule if that water heater 
basic model was manufactured prior to July 13, 2015, and complied with 
the applicable efficiency standards and labeling requirements in effect 
prior to July 13, 2015. (See 42 U.S.C. 6295(e)(5)(K)) Sections III.E 
and III.F explain that DOE intends to address various issues related to 
the transition from the metrics in effect prior to July 13, 2015, 
through the use of enforcement policies.

III. Discussion

A. Purpose

    As discussed in section I, this rulemaking establishes mathematical 
conversion factors that satisfy requirements added to EPCA by AEMTCA. 
(42 U.S.C. 6295(e)(5)) EPCA requires DOE to establish a uniform 
efficiency descriptor for consumer water heaters and commercial water 
heaters, and to establish a mathematical conversion factor to translate 
from the EF, TE, and SL descriptors to the uniform efficiency 
descriptor established by DOE. Id. In the July 2014 test procedure 
final rule, DOE established UEF as the uniform efficiency descriptor, 
and adopted a test method for measuring UEF for consumer and certain 
commercial water heaters. 79 FR 40542 (July 11, 2014). This final rule 
addresses the mathematical conversion factor required by EPCA (see 42 
U.S.C. 6295(e)(5)(E)) and the requirement that the efficiency standard 
be denominated according to the uniform efficiency descriptor (i.e., 
UEF) (see 42 U.S.C. 6295(e)(5)(D)(i)).
    As discussed in the August 2016 SNOPR, DOE reviewed the test 
results used to develop the mathematical conversion factors, and found 
that different water heaters are impacted in different ways by the new 
test method and metric, depending on the specific design and 
characteristics of the water heater. 81 FR 59736, 59741-59742 (August 
30, 2016). Water heaters have numerous attributes that impact energy 
efficiency and performance, and the changes to the test method and 
metrics impact each water heater model differently, often in ways that 
are difficult to predict. For example, two electric water heaters with 
the same rated storage volume, input rating, first-

[[Page 96209]]

hour rating, and energy factor rating (all represented values published 
under the EF test method as indicators of water heater performance) 
were shown by testing to have different measured first-hour ratings and 
uniform energy factors when tested under the new test procedure.
    Given the number of models currently available in the market (756 
unique models at the time of the analysis performed for the August 2016 
SNOPR), it would not be practical to analyze each model individually to 
determine the change in represented values under the new test 
procedure. Rather, DOE analyzed a subset of models that are 
representative of the market as a whole. This approach is consistent 
with the statutory mandate, which instructs DOE to develop ``a 
mathematical conversion factor.'' (42 U.S.C. 6295(e)(5)(E)) In DOE's 
view, the phrase ``mathematical conversion factor'' does not require 
DOE to generate a single number applicable to all water heaters. 
Rather, DOE believes that, despite the use of the word ``factor,'' in 
the singular, the statute permits the use of a conversion equation 
involving several numbers and mathematical operations besides 
multiplication. Still, the phrasing suggests that DOE should develop a 
formula that is broadly applicable, rather than generate a table of 
equivalencies stating the exact UEF equivalent for every individual 
product on the market.
    Because each water heater is impacted differently, it would be 
impossible to develop a single equation, or reasonable set of 
equations, that could be used to model the energy performance of every 
water heater exactly under the new test method. Therefore, DOE 
interprets the statutory mandate for a ``mathematical conversion 
factor'' to call for an equation that will be able to reasonably 
predict a water heater's energy efficiency under the UEF test method 
based on values measured under the EF, TE, or SL test methods for that 
model.
    Any mathematical conversion of that type will have some amount of 
residual difference between predicted and measured values that is 
inherent when applying a mathematical equation (or multiple equations 
for different types of water heaters) to predict the energy efficiency 
performance or delivery capacity of a large set of models. In this 
final rule, DOE sought to reduce the amount of difference between 
predicted and actual performance in several ways. DOE incorporated as 
much test data as was practical and available, and which represented 
models currently on the market. DOE considered several attributes that 
could have a large impact on the test results under both the new and 
old metrics, and included those as appropriate when developing the 
mathematical conversion, which led to a set of equations for water 
heaters with certain different characteristics (e.g., different fuel 
types, different nitrogen oxide (NOX) emissions levels). DOE 
also explored several options for developing the mathematical 
conversion equations (see section III.C for a summary of the approaches 
considered). In addition, DOE sought feedback from interested parties 
and incorporated suggestions for improving the mathematical conversions 
when those suggestions resulted in conversion equations that were 
better predictors of actual measured performance.
    As noted previously, this final rule also addresses the requirement 
that the efficiency standard be denominated in terms of UEF and 
establishes energy conservation standard levels using the UEF metric. 
(42 U.S.C. 6295(e)(5)(D)(i)) As discussed in section I, DOE may not 
adopt a standard that reduces the stringency of the existing standards, 
due to EPCA's ``anti-backsliding'' provisions. (42 U.S.C. 6295(o)(1); 
6313(a)(6)(B)(iii)(I)) Further, EPCA requires that the mathematical 
conversion factor not affect the minimum efficiency requirements. (42 
U.S.C 6295(e)(5)(E)(iii)).
    The methodology used for translating the standards ensures 
equivalent stringency between the existing standards (using EF, TE, and 
SL metrics) and the converted standards (using UEF). Due to differences 
in water heater performance under the different test methods discussed 
in the preceding paragraphs, some models will perform better, and 
others worse, under the new test method than they did under the 
previous test method. In principle, a model that was just above the 
standard level using the old metrics might come out just below the 
converted standard using the conversion factor, and in principle, one 
could regard that result as a change in the standard applicable to that 
particular model. However, such outcomes are unavoidable possibilities 
if DOE is to prescribe a single equation to convert efficiency 
measurements across a product class. As noted above, given the complex 
ways in which detailed design characteristics can affect measurements 
using both the existing protocols and the UEF test procedure, 
specifying EF, TE, and SL for a product does not predict UEF for the 
product with absolute precision. Given that reality, DOE interprets 
section 325 of EPCA as a whole, including the anti-backsliding 
provision and the mandate to develop a conversion factor, to permit 
outcomes in which conversion might shift some products from above to 
below the standard (and some from below to above)--since this is the 
natural and foreseeable consequence of using a conversion factor. 
Because the statute calls for a conversion factor, DOE understands the 
``standard,'' in this context, to refer to the efficiency level 
required on average over a product class. Thus, DOE's goal in 
developing the conversion factor is to ensure that, on average over a 
product class, the standard denominated in UEF corresponds to the same 
maximum energy use and minimum efficiency as the standard denominated 
in EF, TE, and SL.

B. Scope

    This section describes DOE's process for categorizing water heaters 
and establishing the range of units subject to this mathematical 
conversion factor final rule. DOE initially outlined the scope of this 
rulemaking in the April 2015 NOPR. 80 FR 20116, 20122-20124 (April 14, 
2015).
1. Storage Volume and Input Capacity Limitations
    In the NOPR, DOE stated that it was not including water heaters 
that were not previously subject to the test procedures or standards 
for energy factor established in the Code of Federal Regulations in the 
scope of the conversion factor. Id. In the August 2016 SNOPR, DOE 
proposed to make clear its interpretation that the initial consumer 
water heater standards in EPCA \5\ are applicable to the consumer water 
heaters listed in Table III.1 and, accordingly, proposed mathematical 
conversion factors for these water heaters in the August 2016 SNOPR. 81 
FR 59736, 59743 (August 30, 2016).
---------------------------------------------------------------------------

    \5\ The initial energy factor energy conservation standards for 
consumer water heaters established in EPCA are found at 42 U.S.C. 
6295(e)(1), and require that the energy factor be not less than the 
following for products manufactured on or after January 1, 1990:
    Gas Water Heater--0.62-(0.0019 x Rated Storage Volume in 
gallons).
    Oil Water Heater--0.59-(0.0019 x Rated Storage Volume in 
gallons).
    Electric Water Heater--0.95-(0.00132 x Rated Storage Volume in 
gallons).

[[Page 96210]]



   Table III.1--Consumer Water Heaters Not Covered In the NOPR by the
                     Mathematical Conversion Factor
------------------------------------------------------------------------
                                           Description of criteria for
             Product class                  exclusion from conversion
                                                    rulemaking
------------------------------------------------------------------------
Gas-fired Storage......................  Rated Storage Volume >=2 gal
                                          and <20 gal or >100 gal.
Oil-fired Storage......................  Rated Storage Volume >50 gal.
Electric Storage.......................  Rated Storage Volume >=2 gal
                                          and <20 gal or >120 gal.
Tabletop...............................  Rated Storage Volume >=2 gal
                                          and <20 gal or >120 gal.
Gas-fired Instantaneous................  Rated Input <=50,000 Btu/h;
                                          Rated Storage Volume >=2 gal.
Electric Instantaneous.................  Rated Storage Volume >=2 gal.
Oil-fired Instantaneous................  All.
------------------------------------------------------------------------

    In the August 2016 SNOPR, DOE noted that the definitions for 
consumer water heaters added to EPCA under the National Appliance 
Energy Conservation Act of 1987 (NAECA; Pub. L. 100-12 (March 17, 
1987)) do not place any limitation on the storage volume of consumer 
water heaters and do not place a minimum fuel input rate on gas-fired 
instantaneous water heaters. (42 U.S.C. 6291(27)) Thus, DOE proposed to 
make clear its interpretation that the initial standards for water 
heaters added to EPCA cover all consumer water heaters meeting the 
definition of ``water heater'' at 42 U.S.C. 6291(27), regardless of the 
storage volume and without a lower limit on the fuel input rating for 
gas-fired instantaneous water heaters. 81 FR 59736, 59743 (August 30, 
2016).
    The Air-Conditioning, Heating, & Refrigeration Institute (AHRI), 
Bradford White Corporation (Bradford White), A.O. Smith Corporation 
(A.O. Smith), and Rheem Manufacturing Company (Rheem) submitted 
comments opposed to the inclusion of the proposed clarification in the 
August 2016 SNOPR. Those comments were focused primarily on the 
application of standards to consumer water heaters with storage tanks 
of more than 2 gallons (7.6 L) and less than 20 gallons (76 L), with 
commenters stating that the application of standards to these consumer 
water heaters would be inconsistent with DOE's historical treatment of 
such water heaters. (AHRI, No. 27 at p. 7; Bradford White, No. 26 at p. 
2; A.O. Smith, No. 28 at p. 1; Rheem No. 32 at p. 2.) AHRI asserted 
that NAECA codified limitations on the applicability of standards for 
consumer water heaters consistent with the then-current DOE test 
procedure, including the exclusion of storage-type residential water 
heaters less than 20 gallons and greater than 120 gallons. (AHRI, No. 
27 at pp. 7-8) Rheem stated that the test procedures for consumer water 
heaters specifically exempted water heaters with storage tanks of more 
than 2 gallons (7.6 L) and less than 20 gallons (76 L) from being 
covered prior to the UEF test procedure that was finalized in July 2014 
final rule for consumer and certain commercial water heaters. (Rheem, 
No. 32 at p. 2) Rheem added that the August 2016 SNOPR was a departure 
from the April 2015 NOPR, which stated that DOE's current consumer 
water heater test procedures and energy conservation standards are not 
applicable to gas or electric water heaters with storage tanks that are 
at or above 2 gallons (7.6 L) and less than 20 gallons (76 L). (Rheem, 
No. 32 at p. 3) AHRI stated that it understood DOE to be applying 
standards to these products based on the 1990 final rule that adopted 
standards established in EPCA under the NAECA amendments (55 FR 42162 
(Oct. 17, 1990)) and that application of standards to the specified 
products as proposed in the SNOPR would be contrary to EPCA. (AHRI, No. 
27 at p. 8) Bradford White stated that it does not support using only 
input capacity to distinguish between consumer and commercial water 
heaters, and expressed concern that under the proposed clarification, 
water heaters that are currently marketed as commercial products will 
have to be eliminated unless they are able to meet the new UEF 
established for the consumer water heaters. (Bradford White, No. 26 at 
p. 2)
    AHRI also asserted that it is contrary to administrative law and 
unfair to include a proposal to apply the standards to these products 
(i.e., consumer gas-fired storage water heaters with a rated storage 
volume greater than 100 \6\ gallons and consumer electric storage water 
heaters with a rated storage volume greater than 2 gallons and less 
than 20 gallons) at the ``11th hour.'' (AHRI, No. 27 at p. 9) AHRI 
stated that given the thirty-day comment period and DOE's prior 
statements on this issue, manufacturers did not foresee the need to 
spend time or resources to conduct testing and analysis on this 
particular class of products, but instead, the industry devoted its 
limited time and available resources to testing the many products which 
DOE initially identified. (AHRI, No. 27 at p. 9) Rheem stated that 
based on past practice and DOE's statements in the NOPR, it did not 
anticipate the current rulemaking addressing the UEF for the specified 
consumer water heaters, and as a result, the commenter urged DOE to 
address this matter in a separate rulemaking. (Rheem No. 32 at pp. 2-4) 
A.O. Smith also questioned whether the clarification in the August 2016 
SNOPR may violate the letter if not the spirit of the Administrative 
Procedures Act (APA). A.O. Smith viewed the August 2016 test procedure 
SNOPR to represent a change of position, which has placed manufacturers 
in the position of having to respond within thirty days to new 
efficiency standards without knowing if they can meet the standards. 
(A.O. Smith No. 28, pp. 2-3)
---------------------------------------------------------------------------

    \6\ AHRI's comment stated 120 gallons; however, the upper limit 
on storage volume for the energy conservation standards found in 10 
CFR 430.32(d) for consumer gas-fired storage water heaters is 100 
gallons.
---------------------------------------------------------------------------

    DOE acknowledges that it has not previously implemented the 
standards established by NAECA with respect to gas or electric water 
heaters with storage tanks between 2 and 20 gallons in capacity or 
other water heaters listed in Table III.1. However, after careful 
consideration of both the statutory provisions and the comments 
received, DOE is reaffirming its interpretation in the August 2016 
SNOPR that the standards established in EPCA are applicable to the 
water heaters listed in Table III.1. As such, the standards initially 
established by Congress in EPCA are applicable to consumer water 
heaters identified in the August 2016 SNOPR, including those with 
storage tanks that are at or above 2 gallons (7.6 L) and less than 20 
gallons (76 L). As explained in the following paragraphs, this 
interpretation is based on the plain language of EPCA that establishes 
definitions for consumer water heaters and the scope of the 
statutorily-prescribed standards for consumer water heaters, and a 
review of the legislative history reveals no congressional intent to 
the contrary. Nonetheless, as discussed in more detail, DOE will not 
enforce those standards until such time as conversion factors and 
converted standards are

[[Page 96211]]

adopted, which DOE is declining to do in this final rule.
    EPCA, through the amendments made by NAECA, defines ``water 
heater'' for the purpose of delineating which consumer products are 
subject to energy conservation standards. (42 U.S.C. 6291(27); see also 
101 Stat. 103, 104-105) The statutory definition specifies input 
ratings at or below which water heaters are to be classified as 
consumer water heaters (e.g., 75,000 Btu/h for gas-fired storage water 
heaters; 12 kW for electric storage water heaters and electric 
instantaneous water heaters; 210,000 Btu/h for oil-fired instantaneous 
water heaters). The statutory definition of ``water heater'' does not 
provide for any limitation based on storage volume. (42 U.S.C. 
6291(27)) The NAECA amendments also established standards for gas-fired 
consumer water heaters, oil-fired consumer water heaters, and electric 
consumer water heaters, once again without any limitation in terms of 
storage volume. (42 U.S.C. 6295(e)(1); see also 101 Stat. 103, 110)
    AHRI argued that the NAECA amendments imposing standards for water 
heaters do not apply to water heaters smaller than 20 gallons because 
DOE had no test procedures for such products when NAECA was enacted. 
According to AHRI, NAECA ``codified'' DOE's existing test procedures 
``into law,'' and the NAECA standards were ``based on the pre-existing 
EF test procedure.'' DOE does not agree with AHRI's argument that 
Congress intended its statutory standards to be somehow constrained by 
DOE's existing test procedure applicability. DOE had, and retains, the 
discretion to change the test procedures. The provision that AHRI cited 
as ``codif[ying]'' DOE's test procedures--which DOE takes to mean 
adopting them as statute, and thus restricting DOE's authority to alter 
them--did no such thing. AHRI referred to 42 U.S.C. 6293(a); but, as 
amended by NAECA, that provision simply says that ``[a]ll test 
procedures and related determinations . . . which are in effect on the 
date of enactment of [NAECA] shall remain in effect until the Secretary 
amends such test procedures and related determinations.'' The point of 
this provision was to avoid, in a statute that substantially revised 
the substance of DOE's authority to develop test procedures, any 
suggestion that the changes would invalidate pre-existing test 
procedures. The text of the sentence itself makes clear that it did not 
freeze the test procedures into statute; they remained in effect only 
until the Secretary ``amends such test procedures.''
    The NAECA amendments also do not support AHRI's contention that the 
section 6295(e)(1) standards were based specifically on the existing 
test procedure. The statute does not explicitly say the standards 
depended solely on that version of the test procedure. AHRI seems to 
rely on the facts that section 6295(e)(1) prescribed minimum values of 
``energy factor'' and that the NAECA amendments defined ``efficiency 
descriptor,'' which for water heaters was to be expressed as energy 
factor, as the ratio of output and input ``determined using the test 
procedures prescribed under section 323.'' The argument appears to be 
that, for water heaters, ``the test procedures prescribed under section 
323'' meant the test procedures as they existed when NAECA was enacted. 
Thus, AHRI infers, the water heater standards in section 6295(e)(1) 
were minimums for energy factor as the extant test procedures 
determined that value. However, DOE believes it is sounder to read the 
definition of ``efficiency descriptor'' as referring to DOE's test 
procedures as they change over time. Section 323 authorized DOE to 
amend or revise test procedures in appropriate circumstances. It would 
be odd and counterproductive if the concept of ``efficiency 
descriptor'' excluded such updates.
    Fundamentally, if Congress had intended the section 6295(e)(1) 
standards to apply only to products for which DOE had already developed 
test procedures, it could easily have said so. Instead, the statute 
defined ``water heaters'' without a minimum storage capacity; it 
prescribed standards without mention of any minimum; and it invoked a 
metric, energy factor, that was to be measured using test procedures 
that the statute authorized DOE to revise. DOE concludes, therefore, 
that the section 6295(e)(1) were to apply to the full scope of ``water 
heaters'' as soon as DOE issued test procedures reaching that scope. 
Based upon changes in the market and the availability of additional 
data, DOE determined in the July 2014 test procedure final rule (79 FR 
40542, 40545-40549 (July 11, 2014)) that it was appropriate to expand 
the applicability of the water heaters test procedure and thereby 
embrace the full scope of the authority provided by Congress. (42 
U.S.C. 6295(e)(1); see also 101 Stat. 103, 110).
    Based on the foregoing discussion, DOE is reaffirming its 
interpretation in the August 2016 SNOPR that the statutory standards 
apply to the water heaters listed in Table III.1, including those with 
storage volumes between 2 and 20 gallons. DOE acknowledges that its 
long delay in issuing test procedures for such products as well as 
statements it has made in the past may have caused confusion about this 
issue. Coming into compliance with the statutory standards immediately 
would be quite burdensome for industry.
    DOE also received voluminous comments regarding the technical 
merits of the conversion factors and of the converted standards 
expressed in UEF for the water heaters listed in Table III.1, for which 
DOE is going to defer finalizing and implementing these statutory 
standards and further consider the comments. Since DOE is declining to 
adopt mathematical conversion factors and converted standards in UEF in 
this final rule for the water heaters listed in Table III.1, DOE will 
not enforce the statutory standards applicable to the consumer water 
heaters listed in Table III.1 until some point after DOE finalizes the 
conversion factor and the converted standards applicable to those 
products. In doing so, DOE will work with industry on making this 
transition.
2. Water Temperature Limitations
    A.O. Smith expressed concern with DOE's position (adopted in the 
November 2016 commercial water heater test procedure final rule; see 81 
FR 79261, 79286 (Nov. 10, 2016)) that electric water heaters with 
inputs of 12 kW or less are consumer water heaters, regardless of the 
outlet water temperature delivered. A.O. Smith argued that the 
180[emsp14][deg]F delineation serves an important function in the 
marketplace to distinguish between consumer and commercial water 
heaters. (A.O. Smith, No. 28 at p. 2)
    As explained in further detail in the November 10, 2016 commercial 
water heater test procedure final rule, DOE relies on the temperature 
threshold when determining how to distinguish a commercial water heater 
that may be used to serve residential applications (i.e., a 
``residential-duty commercial water heater'') and commercial water 
heaters generally. 81 FR 79261, 79286. Outlet water temperature is one 
of several dividing criteria between those types of commercial models. 
79 FR 40542, 40546 (July 11, 2014). However, DOE has interpreted the 
statute to distinguish between water heaters that are commercial 
equipment under EPCA and those that are consumer products on the basis 
of the rated input, not the delivery temperature. The November 2016 
final rule explained DOE's interpretation on this point, and DOE is not 
revisiting the issue in this final rule. The application of the 
conversion factor

[[Page 96212]]

to residential-duty commercial water heaters is discussed section 
III.B.4. If manufacturers of water heaters have additional inquiries 
they should contact Ashley Armstrong directly using the contact 
information in the ADDRESSES section of this final rule.
3. Grid-Enabled Water Heaters
    As noted in section I, EPCA was recently amended to define and set 
efficiency requirements for grid-enabled water heaters in terms of EF 
(see 42 U.S.C. 6295(e)(6)). EPCA provides that the conversion factor 
may exclude certain covered water heaters from the uniform efficiency 
descriptor if the Secretary determines that the category of water 
heaters does not have a residential use and can be clearly described in 
the final rule, and that the category of water heaters are effectively 
rated using the thermal efficiency and standby loss descriptors. (42 
U.S.C. 6295(e)(5)(F)). Grid-enabled water heaters do have residential 
uses and are not rated using thermal efficiency or standby loss, and 
thus, do not meet the criteria for exclusion from the UEF metric. As a 
result, DOE has developed a conversion factor in this final rule to 
express the standard for these products in terms of UEF. Comments 
related to the conversion factor and converted UEF standards for grid-
enabled water heaters are discussed in sections III.D.2.d and section 
III.D.3.
4. Residential-Duty Commercial Water Heaters
    DOE notes that only commercial water heaters meeting the definition 
of ``residential-duty commercial water heater'' are subject to the 
uniform efficiency descriptor test method, while all other commercial 
water heaters are not. EPCA allows DOE to provide an exclusion from the 
uniform efficiency descriptor for specific categories of otherwise 
covered water heaters that do not have residential uses, that can be 
clearly described, and that are effectively rated using the current 
thermal efficiency and standby loss descriptors. (42 U.S.C. 
6295(e)(5)(F)) In the July 2014 test procedure final rule, DOE 
determined that covered commercial water heating equipment that did not 
meet the definition of a ``residential-duty commercial water heater'' 
met the criteria in EPCA for exclusion from the uniform efficiency 
descriptor. 79 FR 40542, 40545-40547 (July 11, 2014). As a result, this 
final rule only addresses commercial water heaters that meet the 
definition of ``residential-duty commercial water heater.'' This 
definition was recently updated in the November 10, 2016 commercial 
water heater test procedure final rule to remove residential-duty 
classes where definitional criteria preclude the classification of any 
products as residential-duty commercial water heaters within that 
class.\7\ 81 FR 79261, 79321-79322. The definition of ``residential-
duty commercial water heater'' adopted in that final rule includes any 
gas-fired storage, oil-fired storage, or electric instantaneous 
commercial water heater that meets the following conditions:
---------------------------------------------------------------------------

    \7\ For example, DOE has interpreted EPCA to include as consumer 
products electric storage water heaters as having an input of <= 12 
kW. (42 U.S.C. 6291(27)) The previous definition of a residential-
duty water heater excluded any electric storage water heater with an 
input of > 12 kW from being residential-duty. Thus, because all 
electric storage water heaters > 12 kW are not residential-duty, but 
all electric storage water heaters <= 12 kW are consumer water 
heaters, there could not have been a residential-duty commercial 
electric storage water heater. The changes adopted in the commercial 
water heater test procedure final rule amended the definition to 
remove mention of electric storage water heaters, along with several 
other types of water heaters, to prevent confusion.
---------------------------------------------------------------------------

    (1) For models requiring electricity, uses single-phase external 
power supply;
    (2) Is not designed to provide outlet hot water at temperatures 
greater than 180[emsp14][deg]F; and
    (3) Does not meet any of the criteria regarding rated input and 
storage volume presented in Table III.2.

 Table III.2--Capacity Limitations for Defining Commercial Water Heaters
                    Without Residential Applications
                      [i.e., Non-Residential-Duty]
------------------------------------------------------------------------
                                           Indicator of non-residential
           Water heater type                       application
------------------------------------------------------------------------
Gas-fired Storage......................  Rated input >105 kBtu/h; Rated
                                          storage volume >120 gal.
Oil-fired Storage......................  Rated input >140 kBtu/h; Rated
                                          storage volume >120 gal.
Electric Instantaneous.................  Rated input >58.6 kW; Rated
                                          storage volume >2 gal.
------------------------------------------------------------------------

    This final rule establishes mathematical conversion factors for 
gas-fired storage, oil-fired storage, and electric instantaneous 
residential-duty commercial water heaters. DOE also uses the conversion 
factors to express the energy conservation standards for these classes 
of equipment in the UEF metric.

C. Approaches for Developing Conversions

    To develop the conversions between the prior metrics (first-hour 
rating, maximum GPM, energy factor, thermal efficiency, standby loss) 
and the new metrics (first-hour rating, maximum GPM, uniform energy 
factor), DOE considered three different approaches. The first, termed 
``analytical methods,'' uses equations based on the fundamental physics 
of water heater operation to predict how changes in test parameters 
lead to changes in the performance metrics. The second, termed 
``empirical regression,'' is a purely data-driven approach that uses 
experimental data and regressions to develop equations that relate the 
prior metrics to the new ones. The third approach, termed ``hybrid,'' 
uses a regression on the result of an analytical method to account for 
changes in the test procedure not captured by the analytical method.
1. Analytical Methods Approach
    The analytical methods approach relies on basic equations of heat 
transfer and thermodynamics, as well as established understanding of 
the behavior of water heaters, to calculate the metric based on a set 
of known parameters for the water heater, environment, and test 
pattern. Such an approach typically yields an equation or set of 
equations that can be solved to ultimately yield the metric of 
interest, either an efficiency or delivery capacity. An attempt is then 
made to modify the equations for the metrics to yield an equation that 
expresses the new metrics in terms of the old metrics and other known 
quantities. Analytical methods have the advantage of capturing known 
effects on performance without conducting a series of experiments. 
Additionally, a properly formulated relationship would be expected to 
be applicable to all water heaters on the market. Analytical approaches 
do have some drawbacks, however. Most notably, these methods only 
account for

[[Page 96213]]

factors that are known to impact performance and that can be readily 
modeled analytically. There may be other unknown phenomena that affect 
performance that may not be taken into account in the known models. 
Second, application of these models often require assumptions about 
conditions. For example, one may need to assume a particular 
temperature of the water in the water heater despite the fact that it 
is known that there is variation in that temperature. Lastly, while an 
analytical model reduces the amount of tests needed to generate a 
conversion equation, a thorough set of experiments is still necessary 
to validate the model. Because it is based on fundamental physics, 
though, an analytical model can typically be extended with more 
confidence to a water heater that has not been tested than would a 
model based purely on experimental data.
    DOE developed conversion equations based on analytical methods for 
the maximum GPM test (from the maximum GPM under the prior method to 
the current method) and simulated-use tests (i.e., from EF to UEF) for 
all water heaters covered in this rule. DOE created the 
UEFWHAM parameter for consumer water heaters and the 
UEFrd parameter for residential-duty commercial water 
heaters, which represent the converted UEF value for storage water 
heaters using the Water Heater Analysis Model (WHAM) as a basis for the 
conversions, along with several simplifying assumptions. Specifically, 
DOE assumed that the standby heat loss coefficient (UA) and recovery 
efficiency are the same for the EF and UEF test procedure, and that the 
nominal outlet water temperature is a representative approximation of 
the mean temperature of water within the tank. For consumer and 
residential-duty commercial instantaneous water heaters, DOE derived an 
analytical method for the conversion through testing experience and 
commenter feedback. DOE created the UEFmodel and 
UEFmodel,rd parameters, which represent the converted UEF 
value for instantaneous water heaters using the analytical methods 
derived by DOE. DOE presented an in-depth derivation of the analytical 
methods in the August 2016 SNOPR. 81 FR 59736, 59744-59752 (August 30, 
2016).
    For the consumer storage uniform energy factor analytical 
conversion, Bradford White commented that the DOE finding that average 
delivered temperature versus mean tank temperature is higher for 
electric than gas-fired storage water heaters is inconsistent with 
their testing experience and does not fundamentally make sense due to 
water temperature stacking in gas-fired storage water heaters. 
(Bradford White, No. 26 at p. 2) Although DOE acknowledges that there 
is apparently a difference between the testing results observed by 
Bradford White and those observed by DOE, as the August 2016 SNOPR 
explained after discussing several potential assumptions about mean 
tank temperatures, the analytical model that best predicts UEF tested 
values uses the assumption that the mean tank temperature and delivered 
temperature were the same, regardless of fuel type. 81 FR 59736, 59747 
(August 30, 2016). As a result, DOE did not change its assumptions 
related to the mean tank temperature and delivered water temperature 
based on either DOE's data or Bradford White's data, as such changes do 
not appear as though they would improve the accuracy of the conversion 
equation. Bradford White also commented that it does not agree that the 
UA and recovery efficiency will not change with the change in test 
procedure. (Bradford White, No. 26 at p. 2) DOE agrees that UA and 
recovery efficiency are different when testing to the EF test procedure 
than when testing to UEF test procedures, and so stated in the August 
2016 SNOPR in addressing similar comments at that stage. 81 FR 59736, 
59747 (August 30, 2016). DOE also stated that the analytical model that 
best predicts UEF test results uses the assumption that UA and recovery 
efficiency did not change with a change in test procedure. Id. Bradford 
White did not provide any data as would cause DOE to alter the 
tentative conclusion it reached in the August 2016 SNOPR. Accordingly, 
for this final rule, DOE has decided to continue to use the assumption 
that UA and recovery efficiency are the same in both the EF and UEF 
test procedures, as it provides the best prediction of the measured 
UEF. DOE recognizes that this assumption is a simplification of the 
realities of how water heaters operate under the old and new test 
procedures. The use of simplifying assumptions is appropriate in the 
development of an analytical model. The model is not intended to 
capture every aspect of the physical behavior of water and heat in 
these products down to the last detail. Rather, it is meant to provide 
a physically meaningful description that reflects the most significant 
features of water-heater physics and engineering so as to enable DOE to 
develop a mathematically-tractable conversion formula. To serve that 
purpose, DOE considers it appropriate to make simplifying assumptions 
like those regarding UA and recovery efficiency where, as discussed, 
doing so improves rather than decreases the predictive accuracy of the 
model.
    Although, as previously noted, DOE developed a conversion based on 
analytical methods for converting the EF to UEF for all types of water 
heaters, as proposed in the August 2016 SNOPR. For the reasons 
explained in the SNOPR, DOE is choosing in this rule to use the 
analytical method approaches only for: (1) The conversion of maximum 
GPM under the prior test method to maximum GPM under the current test 
method for consumer instantaneous water heaters; and (2) the conversion 
of thermal efficiency and standby loss to UEF for electric 
instantaneous residential-duty commercial water heaters. 81 FR 59736, 
59774 and 59778 (August 30, 2016). For the maximum GPM conversion for 
consumer instantaneous water heaters, DOE concludes that the analytical 
method predicts the resultant data very closely and will broadly apply 
to those units not tested, making it preferable to other approaches. 
For electric instantaneous residential-duty commercial water heaters, 
DOE did not have test data that would be appropriate for use in a 
regression analysis, thereby precluding the use of an empirical 
regression approach or the ``hybrid'' approach that combines an 
analytical method with a regression analysis. For the remaining 
conversion factors, DOE uses either the empirical regression approach 
(see section III.C.2) or the ``hybrid'' approach (see section III.C.3).
2. Empirical Regression Approach
    The second category of conversion factors considered by DOE is 
empirical regression. In this approach, a collection of water heaters 
are tested according to both the former test procedure and the new test 
procedure. The resultant performance metrics, as well as other data on 
the units (e.g., storage volume, input rate), are compiled, and 
statistical techniques are used to create correlations that relate the 
new performance metrics to the prior metrics and characteristics. No 
consideration of the underlying physics is used in this approach. 
Rather, it is purely a data-driven method. The advantage of this 
approach is that the results are not affected by existing assumptions 
on how a water heater should behave under given conditions, with the 
results representing exactly what is observed in actual comparison 
testing. This approach should capture all factors that affect the 
energy efficiency and delivery capacity, even though those factors may 
not be known a priori.

[[Page 96214]]

    Empirical regression also has some drawbacks. One drawback is that 
the resulting equations are most confidently applied to water heaters 
with attributes similar to those that were tested. Consequently, to 
minimize uncertainties, a large sample for testing is often appropriate 
to capture more fully many of the nuances in water heater design. If 
extended to units not sufficiently similar to those that were tested, 
the equations may produce unacceptably large differences between 
predicted and measured values if a feature on the untested model has an 
effect that is not captured in the experimental data. Another major 
drawback is that empirical regression is susceptible to experimental 
uncertainties. While uncertainties can be reduced through careful 
quality checks of experimental data, uncertainty is present in any 
test. The empirical regressions, being based on many samples across 
multiple different units, will further reduce the uncertainty, but some 
amount of uncertainty in the regression may be unavoidable.
    In the April 2015 NOPR and August 2016 SNOPR, DOE noted that it was 
not aware of an analytical method for determining the first-hour 
rating, and proposed to use an empirical regression methodology for 
developing the mathematical conversion factors for first-hour rating. 
DOE believed this approach would be more accurate than attempting to 
develop an analytical method. 80 FR 20116, 20125-20128 (April 14, 2015) 
and 81 FR 59736, 59752 (August 30, 2016). DOE did not receive any 
comments suggesting an alternate methodology for determining first-hour 
rating, and, thus, DOE is establishing conversion factors for those 
metrics and product types based on the use of the empirical regression 
methodology. In the August 2016 SNOPR, DOE found that the conversion 
equations for heat pump water heaters resulting from the analytical 
method (see section III.C.1) and hybrid regressed-analytical approach 
(see section III.C.3) had higher root-mean-square deviation (RMSD) 
values than those resulting from the empirical regression approach. 81 
FR 59736, 59752, 59768 (August 30, 2016). Therefore, for the reasons 
explained in the August 2016 SNOPR and noted above, DOE is establishing 
a mathematical conversion for heat pump water heaters based on the 
empirical regression approach. Finally, for the reasons explained in 
the August 2016 SNOPR (81 FR 59736, 59778 (August 30, 2016)), for 
residential-duty commercial electric instantaneous water heaters, DOE 
has concluded that it is appropriate to assume that the delivery 
capacity would be heavily dependent on the input rating for electric 
instantaneous water heaters, and, thus, DOE developed an equation to 
predict maximum GPM as a function of input rate based on a regression 
analysis.
3. Hybrid Approach
    DOE also analyzed a combination of the analytical methods approach 
and empirical regression approach, termed a hybrid approach. In this 
approach, a broad range of water heaters are tested, as would be done 
in using empirical regression. An additional factor is added to the 
list of attributes that is examined in the regression; this factor uses 
the analytical methods to first estimate the converted value. This 
estimate of the revised performance metric (maximum GPM, first-hour 
rating, or UEF) for each water heater tested is then used as an 
independent variable in a regression to determine the measured UEF. DOE 
believes that this approach takes advantage of the ability of the 
analytical methods approach to capture the major known factors that 
affect the efficiency, yet adds the additional step of regression to 
account for any influences that are not well described by the 
analytical methods. DOE uses this approach for the conversion factors 
adopted to convert from EF to UEF for all types of water heaters except 
for heat pump water heaters, for which the empirical regression 
approach is used (see section III.C.2), and residential-duty commercial 
electric instantaneous water heaters, for which the analytical methods 
approach is used (see section III.C.1).

D. Testing Results and Analysis of Test Data

    DOE used actual test data as part of the basis for the conversion 
factors and to validate the results. DOE selected models for testing 
based on their characteristics being representative of the broader 
market. DOE also used test data supplied by AHRI in developing the 
mathematical conversion factors, and in total, the conversion factors 
prescribed by this final rule are based on test results for 264 basic 
models. The August 2016 SNOPR includes a detailed description of the 
characteristics of the models used in the development of the 
mathematical conversion factors. 81 FR 59736, 59760-59779 (August 30, 
2016).
1. Impact of Certain Water Heater Attributes on Efficiency Ratings
    After conducting testing on all of the selected water heaters 
according to both the prior test procedures and the uniform efficiency 
descriptor test procedure, DOE examined how particular attributes of 
water heaters might affect the conversion factors and investigated the 
approaches discussed in section III.C for obtaining conversion factors. 
The goal of this analysis was to determine whether or not particular 
attributes would warrant separate conversion equations. DOE 
investigated attributes such as: (1) NOX emission level; (2) 
short or tall configuration; (3) vent type; (4) standing pilot versus 
electronic ignition; (5) whether condensing or heat pump technology is 
used; and (6) whether the unit is tabletop. The RMSD between the 
measured values and the values obtained through various conversion 
methods was compared. The conversion approach with the lowest 
cumulative RMSD value for a particular fuel type was considered to be 
the best candidate for the conversion equation.
    No comments were received in response to the August 2016 SNOPR 
suggesting different combinations of water heater attributes to examine 
in regards to the derivation of conversion factors. Accordingly, in 
this final rule, DOE does not change the combination of water heater 
attributes used to derive the mathematical conversion factors. 81 FR 
59736, 59760 (August 30, 2016).
2. Conversion Factor Derivation
    DOE used the methods described in section III.C to derive the 
mathematical conversion factor for the different types of water heaters 
covered within the scope of this rulemaking (as discussed in section 
III.B). This section describes the methodology that was applied to 
develop a conversion factor for each type of water heater.
a. Consumer Storage Water Heaters
    In total, DOE conducted testing of 55 consumer storage water heater 
models using both the EF and UEF test procedures, and likewise, AHRI 
supplied test data for 130 consumer storage water heater models using 
both the EF and UEF test procedures.8 9 In the August 2016 
SNOPR, DOE presented the test data used to derive the consumer

[[Page 96215]]

storage water heater conversion factors and the water heater attributes 
by unit, respectively. 81 FR 59736, 59761-59767 (August 30, 2016).
---------------------------------------------------------------------------

    \8\ The AHRI submitted data points 2-5 and 2-6 were not used in 
this analysis as the reported recovery efficiencies were 98 percent 
and not calculated from test data.
    \9\ If multiple tests were conducted on either the same unit or 
same basic model of a water heater, the results were averaged to 
produce the values reported in this final rule. In one instance 
within the AHRI-submitted data for consumer storage water heaters, 
three tests were conducted, where two tests were conducted on the 
same unit and another test was conducted on a unit of the same basic 
model. The two tests of the same unit were averaged, and this value 
was then averaged with the results of the test of the unit of the 
same basic model.
---------------------------------------------------------------------------

    In response to the August 2016 SNOPR, Bock Water Heaters, Inc. 
(Bock) provided test data for its 32E consumer oil-fired storage water 
heater. Bock stated that the DOE test model labeled in the August 2016 
SNOPR as ``CS-27'' was the most similar to the 32E, but that it was 
unclear if the 32E was the actual unit tested in the SNOPR due to the 
measured first-hour rating under the EF test procedure being well below 
that of 32E. (Bock, No. 29 at p. 1) In response, DOE confirms that CS-
27 was the Bock 32E. DOE reviewed its test data and did not identify 
any errors in the testing, nor does DOE have access to the raw test 
data from Bock to reconcile the difference in results. Therefore, DOE 
treated all three points as valid test points and in order to factor in 
the Bock data, averaged DOE's data point with the test results of the 
two units provided by Bock and derived the conversion factors with this 
updated test data. The test data replacing CS-27 is shown in Table 
III.3.

                                                               Table III.3--Updated Consumer Storage Water Heater Test Data Point
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                                            Prior
                                                                                                   Storage     Input rate     Prior FHR    Updated FHR    recovery
                 CS No.                           AHRI No.                      Type            volume (gal)     (Btu/h)        (gal)         (gal)      efficiency        EF            UEF
                                                                                                                                                             (%)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
27.....................................  N/A.......................  Oil......................         30.2       103,800         153.3         128.5          91.6         0.621         0.641
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

    For consumer storage water heaters, DOE used the regression method 
described in section III.C.2 to predict first-hour ratings (FHRs) under 
the UEF test procedure to be used in the conversion to UEF since DOE is 
not aware of an ``analytical approach'' that can be used to predict 
first-hour ratings. Of the factors considered, DOE found that the 
first-hour rating determined under the EF test procedure was the best 
overall predictor of the new first-hour rating. These findings were 
based on the RMSDs between predicted and measured values. The resulting 
equations for determining the new FHR of consumer storage water heaters 
are presented in Table III.4.

 Table III.4--Consumer Storage Water Heater First-Hour Rating Conversion
                            Factor Equations
------------------------------------------------------------------------
                                  Distinguishing
         Product class               criteria        Conversion factor
------------------------------------------------------------------------
Consumer Gas-fired Water        Non-Condensing,    New FHR = 7.9592 +
 Heater.                         Standard or Low    0.8752 x FHRP.
                                 NOX.
                                Non-Condensing,    New FHR = 25.0680 +
                                 Ultra-Low NOX.     0.6535 x FHRP.
                                Condensing.......  New FHR = 1.0570 x
                                                    FHRP.
Consumer Oil-fired Water        N/A..............  New FHR = 0.9102 x
 Heater.                                            FHRP.
Consumer Electric Water Heater  Electric           New FHR = 9.2827 +
                                 Resistance.        0.8092 x FHRP.
                                Tabletop.........  New FHR = 41.5127 +
                                                    0.1989 x FHRP.
                                Heat Pump........  New FHR = -4.2705 +
                                                    0.9947 x FHRP.
------------------------------------------------------------------------

    In the equations, ``New FHR'' is the predicted first-hour rating 
that would result under the UEF test method and is used for conversion 
to UEF; ``FHRP'' is the first-hour rating determined under 
the EF test procedure, and the slope and intercept are constants 
obtained from a linear regression. While most of the data allowed for 
such a regression fit, in two cases (condensing gas-fired and oil-
fired) the available data were too limited to produce reliable 
regressions for the full set of parameters. To constrain the regression 
so as to generate more reliable predictions for those smaller sets of 
data, the intercepts of the regressions were assigned a value of zero, 
meaning that a water heater with an FHRP of zero would also 
have a New FHR of zero. This assignment is reasonable because if a 
hypothetical water heater were not able to deliver any water under the 
EF test procedure, it also would not be able to deliver water under the 
UEF test procedure.
    Bock commented that the first-hour rating conversion proposed in 
the SNOPR for consumer oil-fired water heaters was different in both 
direction and magnitude from its supplied test data and requested the 
conversion be reexamined. (Bock, No. 29 at p. 2) DOE notes, however, 
that the conversion factor must cover a range of water heaters, 
including models from manufacturers other than Bock. That the 
conversion is not the same as what one would get from Bock's tests 
alone does not invalidate it.
    In response to the first-hour rating mathematical conversion 
developed in the SNOPR, Bradford White commented that the conversion is 
too inaccurate, but that it did not have an alternative suggestion. 
(Bradford White, No. 26 at p. 3) AHRI commented that the inaccuracy of 
the conversion causes models be converted to bins to which they were 
not tested. (AHRI, No. 27 at p. 6) In response, DOE notes that it 
explored several possible conversions for developing the first-hour 
rating conversion. The best trend was observed based on a regression as 
a function of first-hour rating. The average RMSD value resulting from 
this approach (7.73 gallons) is the lowest RMSD observed in the FHR 
analysis, and DOE is unaware of any approaches that would result in 
lower RMSDs. DOE received no comments suggesting methods that would 
result in a lower RMSD for the first-hour rating conversion. DOE 
acknowledges that some models can have a converted FHR that would 
classify it into one draw pattern and a tested FHR that would classify 
it into another as a result of the difference inherent with a 
mathematical representation of a physical system. DOE views such a 
result as unavoidable; as discussed above in section III.A, any 
conversion formula applied to a broad set of models will leave some 
residual differences for many models. Those differences can push a 
model at the edge of one category into another. However, DOE will not 
take enforcement action regarding such a model if there is adherence to 
the provisions discussed in section III.E. For models entering the 
market after July 13, 2015, representations will have to be based on 
tested UEF values, and the appropriate

[[Page 96216]]

energy conservation standards set forth in section III.D.3 will need to 
be met. Thus, for such units, the issue of a converted FHR value 
resulting in classification into the wrong draw pattern bin is not 
applicable.
    After determining the converted first-hour rating, the next step in 
the conversion process is to determine which draw pattern is to be 
applied to convert from EF to UEF. After the first-hour rating under 
the uniform efficiency descriptor is determined using the conversion 
factor above, that value can be applied to determine the appropriate 
draw pattern bin (i.e., very small, low, medium, or high) using Table 1 
of the uniform efficiency descriptor test procedure. 10 CFR part 430, 
subpart B, appendix E, section 5.4.1. In the August 2016 SNOPR, DOE 
proposed to use the ``hybrid approach'' for all non-heat pump water 
heaters and the ``empirical regression approach'' for heat pump water 
heaters. 81 FR 59736, 59768 (August 30, 2016). DOE received no comments 
on the SNOPR regarding these conversion approaches and has, therefore, 
for the reasons provided in the August 2016 SNOPR, adopted the 
conversion factors found in Table III.6. DOE notes that the UEF 
conversion factor for consumer oil-fired storage water heaters has been 
updated based upon the addition of the Bock test data.
    With the draw bin known, the UEF value based on the WHAM analytical 
model (i.e., UEFWHAM) can be calculated using the equation 
and the coefficient values presented in Table III.5 for all consumer 
non-heat pump storage water heater types, where EF is the energy 
factor; [eta]r is the recovery efficiency in decimal form; 
and P is the input rate in Btu/h. The UEF value can be calculated for 
heat pump storage water heater using the equation in Table III.6, which 
does not rely on the UEFWHAM value from the analytical 
model.
[GRAPHIC] [TIFF OMITTED] TR29DE16.000


  Table III.5--Coefficients for the Analytical UEF Conversion Factor for Consumer Storage Water Heaters, Except
                                    Consumer Heat Pump Storage Water Heaters
----------------------------------------------------------------------------------------------------------------
                  Draw pattern                           a               b               c               d
----------------------------------------------------------------------------------------------------------------
Very Small......................................        0.250266            57.5        0.039864            67.5
Low.............................................        0.065860            57.5        0.039864            67.5
Medium..........................................        0.045503            57.5        0.039864            67.5
High............................................        0.029794            57.5        0.039864            67.5
----------------------------------------------------------------------------------------------------------------

    In the equations in Table III.6, UEFWHAM is a predicted 
value of UEF calculated based on the WHAM analytical model, EF is the 
measured energy factor, and DV is the drawn volume in gallons.

      Table III.6--Consumer Storage UEF Conversion Factor Equations
------------------------------------------------------------------------
                                  Distinguishing
         Product class               criteria        Conversion factor
------------------------------------------------------------------------
Consumer Gas-fired Water        Non-Condensing,    New UEF = -0.0002 +
 Heater.                         Standard or Low    0.9858 x UEFWHAM.
                                 NOX.
                                Non-Condensing,    New UEF = 0.0746 +
                                 Ultra-Low NOX.     0.8653 x UEFWHAM.
                                Condensing.......  New UEF = 0.4242 +
                                                    0.4641 x UEFWHAM.
Consumer Oil-fired Water        N/A..............  New UEF = - 0.0033 +
 Heater.                                            0.9528 x UEFWHAM.
Consumer Electric Water Heater  Conventional.....  New UEF = 0.4774 +
                                                    0.4740 x UEFWHAM.
                                Tabletop.........  New UEF = - 0.3305 +
                                                    1.3983 x UEFWHAM.
                                Heat Pump........  New UEF = 0.1513 +
                                                    0.8407 x EF + 0.0043
                                                    x DV.
------------------------------------------------------------------------

b. Consumer Instantaneous Water Heaters
    DOE tested 22 consumer instantaneous water heaters to both the EF 
and UEF test procedures, and AHRI supplied test data for 36 additional 
units of this water heater type.10 11 DOE presented the 
consumer instantaneous water heater test data and attributes in the 
August 2016 SNOPR. 81 FR 59736, 59773-59774 (August 30, 2016).
---------------------------------------------------------------------------

    \10\ The AHRI submitted test data point identified as ``CIS-5'' 
was not used because the measured input rate was greater than the 
maximum allowable deviation from the rated input rate of 2 percent, 
resulting in an invalid test.
    \11\ To avoid weighting individual basic models more heavily 
than others in the development of the conversion factors, if 
multiple tests were conducted on either the same unit or same basic 
model of a water heater, the results were averaged to produce the 
values reported in the SNOPR. 81 FR 59736, 59773 (August 30, 2016). 
In one instance within the AHRI-submitted data for consumer 
instantaneous water heaters, three tests were conducted, where two 
tests were conducted on the same unit and another test was conducted 
on a unit of the same basic model. The two tests of the same unit 
were averaged, and this value was then averaged with the results of 
the test of the unit of the same basic model.
---------------------------------------------------------------------------

    As proposed in the August 2016 SNOPR, DOE used an analytical method 
(see III.C.1) to convert the prior measured values of maximum GPM 
rating for consumer instantaneous water heaters to the measured values 
under the uniform efficiency descriptor test procedure, because it 
predicts the resultant data very closely and will broadly apply to 
those units not tested. 81 FR 59736, 59774 (August 30, 2016). As 
discussed in section III.C.1, DOE also developed an analytical method 
to estimate the change in prior measured values of energy factor under 
the energy factor test procedure to measured values of uniform energy 
factor under the uniform efficiency descriptor test procedure. DOE 
found that using the ``hybrid approach,'' which combined the DOE-
developed analytical method with a regression analysis based on 
measured UEF test data (as described in III.C.3), resulted in the 
lowest RMSD value and proposed to use that conversion factor in the 
August 2016

[[Page 96217]]

SNOPR. Id. DOE received no comments on the consumer instantaneous water 
heater conversion factors and, therefore, for the reasons given in the 
SNOPR, adopts the conversion factors proposed in the August 2016 SNOPR, 
as shown in Table III.8. In the equations in Table III.8, Max 
GPMP is the maximum GPM based on the prior DOE test 
procedure, and UEFmodel is the predicted UEF determined 
using the analytical model.
    With the draw bin known, the UEFmodel value can be 
calculated using the equation and the coefficient values presented in 
Table III.7 below for all consumer instantaneous water heater types, 
where [eta]r is the recovery efficiency expressed in decimal 
form, and A is dependent upon the applicable draw pattern and fuel 
type.
[GRAPHIC] [TIFF OMITTED] TR29DE16.001


 Table III.7--Coefficients for the Analytical UEF Conversion Factor for
                  Consumer Instantaneous Water Heaters
------------------------------------------------------------------------
                                                         A
              Draw pattern               -------------------------------
                                             Electric           Gas
------------------------------------------------------------------------
Very Small..............................        0.003819        0.026915
Low.....................................        0.001549        0.010917
Medium..................................        0.001186        0.008362
High....................................        0.000785        0.005534
------------------------------------------------------------------------


   Table III.8--Consumer Instantaneous UEF Conversion Factor Equations
------------------------------------------------------------------------
             Product class                      Conversion factor
------------------------------------------------------------------------
All Consumer Instantaneous.............  New Max GPM = 1.1461 x Max
                                          GPMP.
Gas-fired Instantaneous................  New UEF = 0.1006 + 0.8622 x
                                          UEFmodel.
Electric Instantaneous.................  New UEF = 0.9847 x UEFmodel.
------------------------------------------------------------------------

c. Residential-Duty Commercial Water Heaters
i. Gas-fired Storage and Oil-fired Storage
    DOE tested 8 residential-duty commercial storage water heaters to 
both the thermal efficiency and standby loss and UEF test procedures, 
and AHRI supplied test data for 12 additional units.\12\ The August 
2016 SNOPR presented the attributes and test results for residential-
duty commercial storage water heaters used in the development of the 
conversion factors. 81 FR 59736, 59776-59777 (August 30, 2016).
---------------------------------------------------------------------------

    \12\ If multiple tests were conducted on either the same unit or 
same basic model of a water heater, the results were averaged to 
produce the values reported in the August 2016 SNOPR. 81 FR 59736, 
59776 (August 30, 2016).
---------------------------------------------------------------------------

    DOE is not aware of an analytical method to use the measured values 
from the thermal efficiency and standby loss tests conducted under the 
prior commercial water heater test procedure to estimate the first-hour 
rating under the new test procedure. Therefore, DOE used the empirical 
regression approach (see section III.C.2) along with the best 
combination of water heater attributes to determine the first-hour 
rating conversion factor. The empirical regression for converting 
first-hour ratings presented in the August 2016 SNOPR was based on 
thermal efficiency and rated storage volume. 81 FR 59736, 59777 (August 
30, 2016). DOE clarifies here that the storage volumes used in the 
empirical regression were measured storage volumes. The equations in 
Table III.10 and in the regulatory text have been updated to reflect 
this clarification. The next step in the conversion is to determine 
which draw pattern must be applied to convert to UEF. After the first-
hour rating under the uniform efficiency descriptor is determined 
through the first-hour rating conversion factor, the converted value 
can be applied to determine the appropriate draw pattern bin (i.e., 
very small, low, medium, or high) using Table 1 of the uniform 
efficiency descriptor test procedure. 10 CFR part 430, subpart B, 
appendix E, section 5.4.1. In the August 2016 SNOPR, DOE proposed to 
use the hybrid approach (see section III.C.3) to calculate the 
residential-duty commercial storage water heater conversion factor for 
the uniform energy factor. 81 FR 59736, 59777 (August 30, 2016). DOE 
received no comments on the uniform energy factor conversion for 
residential-duty commercial storage water heaters and for the reasons 
given in the SNOPR, continues use of the hybrid approach in this final 
rule. Therefore, the resulting conversion factors adopted in this final 
rule are the same as those proposed in the August 2016 SNOPR, and are 
shown in Table III.10.
    With the draw bin known, the UEFrd value (i.e., the 
predicted UEF value from the analytical method alone) can be calculated 
using the equation and the coefficient values presented in Table III.9 
below for all residential-duty commercial storage water heater types, 
where P is the input rate in Btu/h; Et is the thermal efficiency; SL is 
the standby loss in Btu/h; and F and G are coefficients as specified in 
the table below based on the applicable draw pattern.
[GRAPHIC] [TIFF OMITTED] TR29DE16.002


[[Page 96218]]



 Table III.9--Coefficients for the Analytical UEF Conversion Factor for
            Residential-Duty Commercial Storage Water Heaters
------------------------------------------------------------------------
              Draw Pattern                       F               G
------------------------------------------------------------------------
Very Small..............................        0.821429       0.0043520
Low.....................................        0.821429       0.0011450
Medium..................................        0.821429       0.0007914
High....................................        0.821429       0.0005181
------------------------------------------------------------------------

    In Table III.10, Vm is the measured storage volume, in 
gallons.

 Table III.10--Residential-Duty Commercial Storage UEF Conversion Factor
                                Equations
------------------------------------------------------------------------
             Product class                      Conversion factor
------------------------------------------------------------------------
All Residential-Duty Commercial Storage  New FHR = - 35.8233 + 0.4649 x
 Water Heaters.                           Vm + 160.5089 x Et.
                                         New UEF = - 0.0022 + 1.0002 x
                                          UEFrd.
------------------------------------------------------------------------

ii. Electric Instantaneous
    As stated in the August 2016 SNOPR, the maximum GPM conversion for 
residential-duty commercial electric instantaneous water heaters was 
found using the empirical regression approach (see section III.C.2), 
and the uniform energy factor conversion was found using the analytical 
methods approach (see section III.C.1). 81 FR 59736, 59778 (August 30, 
2016). DOE received no comments about the maximum GPM or UEF 
conversions for residential-duty commercial electric instantaneous 
water heaters, and, therefore, for the reasons given in the August 2016 
SNOPR, adopts the equations below, where Q is the input rate in kBtu/h; 
Et is the thermal efficiency; and A is found using the 
coefficients presented in Table III.11. The appropriate draw pattern 
bin (i.e., very small, low, medium, or high) can be found by using the 
converted New Max GPM value and Table 1 of the uniform efficiency 
descriptor test procedure. 10 CFR part 430, subpart B, appendix E, 
section 5.4.1. There is no further UEF conversion equation needed, as 
the analytical method was used directly, rather than the ``hybrid'' 
regression-analytical approach used for other water heaters, and 
UEFrd,model is equal to the New UEF.

New Max GPM = 0.0146 + 0.0295 *Q

[GRAPHIC] [TIFF OMITTED] TR29DE16.003


 Table III.11--Coefficients for the Analytical UEF Conversion Factor for
    Residential-Duty Commercial Electric Instantaneous Water Heaters
------------------------------------------------------------------------
                      Draw pattern                               A
------------------------------------------------------------------------
Very Small..............................................        0.003819
Low.....................................................        0.001549
Medium..................................................        0.001186
High....................................................        0.000785
------------------------------------------------------------------------

d. Grid-Enabled Storage Water Heaters
    EPCA defines a ``grid-enabled water heater'' as an electric 
resistance water heater that has a rated storage volume above 75 
gallons, is equipped with an activation lock that prevents the water 
heater from delivering more than 50 percent of the rated first-hour 
rating unless unlocked, and bears a permanent label advising end-users 
of the intended and appropriate use of the product. (42 U.S.C. 
6295(e)(6)(A)(ii))
    At the time of the analysis for the SNOPR, DOE was unable to 
identify any grid-enabled water heaters available on the market which 
met the statutory definition, nor does it have test data specific to 
grid-enabled water heaters. However, due to the similarities in design 
between grid-enabled water heaters (which by definition are electric 
resistance water heaters) and consumer electric storage water heaters 
below 55 gallons that use electric resistance elements, DOE based its 
proposed conversion factor and energy conservation standard derivation 
for grid-enabled water heaters on the consumer electric storage water 
heater test data and the associated conversions for below-55-gallon 
consumer electric storage water heaters. 81 FR 59736, 59778-59779 
(August 30, 2016).
    In response, A.O. Smith commented that while the commenter would 
have preferred using test data from electric storage water heaters at 
or above 75 gallons, DOE's approach to the conversion was reasonable. 
(A.O. Smith, No. 28 at p. 5) In contrast, the NRECA Joint Stakeholders 
\13\ stated that the conversion for grid-enabled water heaters should 
be based on real test data and that there was not enough time to review 
the conversion. (NRECA Joint Stakeholders, No. 30 at p. 2) Similarly, 
Rheem stated that the differences in design and functionality from 
regular electric resistance water heaters to grid-enabled water heaters 
resulting from the additional requirements on grid-enabled water 
heaters (e.g., the activation lock), as well as the change in storage 
volume, may affect test results, and this cannot be represented through 
data extrapolation and regression analysis. Rheem further stated that 
it expects grid-enabled models to be introduced into the market in the 
near term, and suggested that DOE should postpone the development of a 
conversion factor for grid-enabled water heaters until such time that 
test data can be used to derive the conversion. (Rheem, No. 32 at pp. 
4-6) In addition, AHRI and several manufacturers raised concerns 
regarding the test method for grid-enabled water heaters. AHRI stated 
that the UEF test procedure does not clearly specify how the activation 
lock first-hour rating requirement will be validated or how

[[Page 96219]]

the thermostat should be set for a grid-enabled water heater. (AHRI, 
No. 27 at p. 3) A.O. Smith and Rheem supported AHRI's test procedure 
comments and urged DOE to adopt a specific method of test for grid-
enabled water heaters. (A.O. Smith, No. 28 at p. 4; Rheem, No. 32 at p. 
5)
---------------------------------------------------------------------------

    \13\ The National Rural Electric Cooperative Associations 
(NRECA) submitted a comment on behalf of itself, the Natural 
Resources Defense Council, Edison Electric Institute, Steffes 
Corporation, Rheem Manufacturing Company, Vaughn Thermal 
Corporation, and American Public Power Association under the title 
``Joint Stakeholders.'' This comment is referred to as ``NRECA Joint 
Stakeholders'' throughout this final rule, as another joint comment 
was also submitted.
---------------------------------------------------------------------------

    Since the publication of the August 2016 SNOPR, four models of 
grid-enabled storage water heaters have been added to the AHRI 
database.\14\ DOE was able to find product literature published on the 
manufacturer's Web site for only one the four models, which is 
manufactured by Vaughn. The Vaughn model is an 80-gallon electric 
resistance water heater with an input of 4.5 kW and an EF of 0.93. 
Product literature indicates the model has 3 inches of polyurethane 
foam insulation, two heating elements, and is equipped with a software 
activation lock to prevent the unit being used outside of a utility-
sponsored load management or demand response program.\15\ As one would 
expect, this model appears to be essentially the same as an electric 
resistance storage water heater, but with an activation lock control 
that limits the capacity unless the unit is used in a utility-sponsored 
load management or demand response program. DOE has no reason to expect 
that future designs for grid-enabled water heaters would differ 
significantly from Vaughn's design, and after considering the design of 
the grid-enabled water heater currently on the market from Vaughn, DOE 
disagrees that there are significant differences in design and 
functionality between regular electric resistance water heaters and 
grid-enabled water heaters that would affect the results under either 
the old or the current test procedure. DOE notes that a typical 
consumer electric water heater at or below 55 gallons would have a 
rated input of 4.5 kW, two resistance heating elements, and three to 
four inches of insulation, which is similar to the characteristics of 
the Vaughn model. One significant difference is the change in storage 
volume; however, DOE continues to conclude that the difference is a 
matter of scale, not technology, and, thus, would be well modeled by 
the WHAM analytical model. Further, DOE tested one 80 gallon electric 
storage water heater (which, as noted above, is expected to be similar 
in design to grid-enabled water heaters), and the measured UEF for the 
high draw pattern was 0.94, which is greater than the UEF standard 
level proposed in the August 2016 SNOPR of 0.92 for this size unit. 81 
FR 59736, 59784 (August 30, 2016).
---------------------------------------------------------------------------

    \14\ See: https://www.ahridirectory.org/ahridirectory/pages/home.aspx.
    \15\ See: http://www.vaughncorp.com/utilities/.
---------------------------------------------------------------------------

    Regarding concerns related to the applicability of the test 
procedure, DOE notes that there is no separate test method for grid-
enabled water heaters. Grid-enabled water heaters should be tested 
pursuant to the test procedure in Appendix E to Subpart B of part 430. 
As discussed above, DOE expects that designs for grid-enabled water 
heaters will, for the most part, consist of an electric resistance 
storage water heater that is equipped with a control mechanism to limit 
the capacity until activated by a utility company (i.e., an activation 
lock). Thus, DOE sees no reason why the current Federal test method 
would not be applicable and representative of grid-connected water 
heaters. DOE believes manufacturers may have questions regarding set-up 
of grid-connected water heaters pursuant to the test method for which 
DOE is willing to work through. To the extent that the current test 
procedure is inapplicable, any interested person may submit a petition 
for waiver for a particular basic model from any requirements of the 
Federal test procedure, upon the grounds that the basic model contains 
one or more design characteristics which either prevent testing of the 
basic model according to the prescribed test procedures or cause the 
prescribed test procedures to evaluate the basic model in a manner so 
unrepresentative of its true energy and/or water consumption 
characteristics as to provide materially inaccurate comparative data. 
10 CFR 430.27(a)(1).
    After considering the comments, DOE has decided to use the 
conversion factors for consumer electric storage water heaters below 55 
gallons of storage volume for grid-enabled water heaters as initially 
proposed in the August 2016 SNOPR and shown below. In the equation for 
the converted first-hour rating (``New FHR''), FHRP is the 
first-hour rating based on the EF test procedure in gallons. The 
converted UEF (``New UEF'') equation is based on the UEFWHAM 
(resulting from the analytical method), which is calculated as shown in 
the equation below where [eta]r is the recovery efficiency 
based on the EF test procedure, P is the input rate in Btu/h, and a, b, 
c, and d are coefficients to the WHAM analytical model and can be found 
using Table III.5.

New FHR = 9.2827 + 0.8092 x FHRP
[GRAPHIC] [TIFF OMITTED] TR29DE16.004

New UEF = 0.4474 + 0.4740 x UEFWHAM

3. Energy Conservation Standard Derivation
    After developing the mathematical conversion factors to convert 
from the prior tested values under the EF metric to the tested values 
under the UEF metric, DOE used the conversion factors to translate the 
energy conservation standards to be in terms of UEF. In the August 2016 
SNOPR, DOE developed a methodology for translating the existing energy 
conservation standards to UEF, termed the ``representative model'' 
method. 81 FR 59736, 59779-59780. The ``representative model'' method, 
consists of the following steps for determining the minimum UEF 
standard:
    1. Using the DOE compliance certification database and AHRI 
Directory, for minimally-compliant models, determine the unique rated 
storage volumes available on the market prior to July 13, 2015 (the 
date on which DOE's requirement that rated storage volume equal the 
mean of the measured storage volume was effective).\16\
---------------------------------------------------------------------------

    \16\ As discussed in section III.D.3.a, in the July 2014 final 
rule, DOE amended the certification requirements for consumer water 
heaters to specify that the rated storage volume of a water heater 
must be the mean of the storage volumes measured over the sample of 
tested units. 79 FR 40542, 40565-40566 (July 11, 2014)
---------------------------------------------------------------------------

    2. For each rated storage volume identified in step 1, find average 
values of conversion factor inputs (i.e., input rating and recovery 
efficiency for consumer water heaters (except consumer heat pump water 
heaters), and input rating for residential-duty commercial water 
heaters) for minimally-compliant basic models in each product class. 
(For product classes where no minimally-compliant models exist on the 
market, DOE used other

[[Page 96220]]

methods to estimate the characteristics of minimally-compliant models, 
which were discussed in detail in the August 2016 SNOPR. 81 FR 59736, 
59780-59782 (August 30, 2016))
    3. Calculate the energy conservation standard (in terms of energy 
factor for consumer water heaters and thermal efficiency/standby loss 
for residential-duty commercial water heaters (with input rate for 
determining standards found from step 2)) for each product class based 
on the rated storage volume, as reported in the DOE compliance 
certification database and AHRI Directory at the time of this analysis 
(before DOE's requirement that rated storage volume equal the mean of 
the measured storage volume was effective).
    4. Using applicable average values for conversion factor inputs 
determined in step 2 and the applicable minimum energy conservation 
standards calculated in step 3, calculate the equivalent UEF for 
minimally-compliant models at each discrete rated storage volume 
(determined in step 1) using the appropriate conversion factor for the 
product class.
    5. Adjust the rated storage volumes to estimate the rated storage 
volume that would reflect DOE's requirement at 10 CFR 
429.17(a)(1)(ii)(C) that rated storage volume equal the mean of the 
measured storage volume of all units within the sample. DOE estimated 
that for electric storage water heaters, the rated storage volume would 
decrease by 10 percent, and for gas-fired and oil-fired water heaters, 
the rated storage volume would decrease by 5 percent.
    6. For each product class and draw pattern, using a simple 
regression, find the slope and intercept where the independent variable 
is the range of adjusted rated storage volumes (determined in step 5) 
and the dependent variable is the UEF values associated with the rated 
storage volumes and specific draw pattern calculated in step 4.
    AHRI commented that for models at a discrete rated volume and with 
equivalent efficiency characteristics, the highest input rate should be 
used instead of the average input rate, as a higher input rate would 
result in a lower measured EF or UEF. AHRI commented further that DOE 
should release the actual derivations of the values used by DOE, as it 
believes the use of average input rates reflects an error in the DOE 
analysis. (AHRI, No. 27 at p. 3) DOE notes that the ``representative 
model'' method was not intended to analyze the worst-case EF or UEF at 
a particular volume, but rather to examine typical units that are 
representative of minimally compliant models at that volume. Thus, this 
method does not ensure all models on the market convert to at or above 
the standards. Rather, as the last step is the application of a linear 
regression, some of the representative models will be below the 
standards. This corresponds to the potential for some models on the 
market to have UEF ratings below the converted standards, which is to 
be expected as discussed in section III.A. Models that fall below the 
converted UEF standards may qualify for DOE's enforcement policy, as 
discussed in section III.E. Thus, DOE continued to use a representative 
value for the input rate in its calculations, rather than using the 
maximum input rate as suggested by AHRI. Based on the other comments 
received from AHRI and other stakeholders, in regards to the 
mathematical method DOE implemented and discussed subsequently in the 
next paragraph, DOE does not believe releasing the actual derivations 
would provide any benefit to the analysis. DOE has released the summary 
data in docket for each step in the rulemaking process such that its 
data is transparent and the results of the calculations are published 
as well. Any stakeholder can run a regression analysis in Excel on the 
dataset it wishes to mirror. Minor adjustments to specific standard 
levels were requested and addressed independently.
    Several commenters submitted an analysis of converted UEF values 
based on published data, and compared those values to the proposed UEF 
standards. DOE notes that many of the comments received in response to 
the SNOPR appear to contain calculation errors. Thus, DOE seeks to 
clarify the process for applying the conversion factors, and has 
slightly re-organized the regulatory text at the end of this document 
in an attempt to clarify the process for applying the conversion 
factors. When converting the first-hour rating or maximum GPM values, 
apply the appropriate delivery capacity conversion equation, and round 
to the nearest gallon for the converted first-hour rating and nearest 
0.1 gpm for the converted maximum GPM. Use this rounded delivery 
capacity value to determine the appropriate draw pattern bin (very 
small, low, medium, or high) as initially specified in either Table 1 
or Table 2 of the uniform efficiency descriptor test procedure, and as 
also adopted in 10 CFR 429.17 in this final rule. 10 CFR part 430, 
subpart B, appendix E, section 5.4.1. With the draw pattern known, 
apply the appropriate UEF conversion for that draw pattern and water 
heater type, and round the result to the hundredths decimal place. To 
calculate the applicable minimum EF standard for a particular model, 
use the rated storage volume, as determined before July 13, 2015 (i.e., 
before the requirement that the rated storage volume equal the mean of 
the measured storage volumes from testing was applicable) directly in 
the applicable equation. To calculate the minimum UEF for a particular 
model, either use the measured storage volume from testing or, if that 
information is not available, correct the rated storage volume to 
approximate the rated storage volume under the requirement that the 
rated storage volume be the mean of the measured volumes of the test 
sample. For electric storage water heaters and fossil fuel-fired 
storage water heaters, DOE applied a 10 percent and 5 percent decrease, 
respectively, to the rated storage volume to approximate the measured 
storage volume. Round the approximated measured storage volume to the 
nearest gallon, and use it to determine the minimum UEF requirement. 
Round the minimum EF and UEF values to the hundredths decimal place. 
DOE notes that in order to de-identify the models tested, the August 
2016 SNOPR did not present rated values, so commenters, therefore, 
could not determine the minimum EF standard (as they did not have the 
rated storage volume) or compare the measured EF results to the rated 
EF. Minimum UEF values could be determined by using the stated measured 
storage volume rounded to the hundredths decimal place. In the 
discussion below, when comparing either a measured or converted EF or 
UEF value to the appropriate energy conservation standard, all values 
have been rounded to the hundredths decimal place.
    California Investor Owned Utilities \17\ (CA IOUs) stated that they 
support the proposed conversion equations. (CA IOUs, No. 25 at p. 2) 
ASAP Joint Stakeholders \18\ provided a table with the number of 
models, by water heater type, in the AHRI Directory that did not meet 
the proposed UEF standards after having the appropriate conversion 
factors applied. The ASAP Joint

[[Page 96221]]

Stakeholders stated that the distribution of non-compliant models is 
not evenly distributed across the water heater product classes, and in 
particular, that DOE should reexamine its converted standard for 
tabletop water heaters. For all other product classes, the ASAP Joint 
Stakeholders commented in support of the proposed conversions. (ASAP 
Joint Stakeholders, No. 31 at pp. 1-3) Rheem also stated that none of 
the tabletop water heaters convert to pass the proposed standards and 
requested the levels be decreased by 0.04. (Rheem, No. 32 at p. 11) DOE 
examined the commenters' results for tabletop water heaters and 
believes that the commenters made an error in the calculation of non-
complying models. After applying the proposed conversions for consumer 
electric storage and tabletop water heaters, DOE found that no models 
would have converted UEF values below the proposed UEF standards. 
However, for all other water heater types, DOE found similar results to 
those reported by ASAP Joint Stakeholders. Therefore, DOE has 
determined that no adjustments to the proposed energy conservation 
standards for tabletop storage water heaters are necessary.
---------------------------------------------------------------------------

    \17\ Pacific Gas and Electric Company, Southern California Gas 
Company, San Diego Gas and Electric, and Southern California Edison 
collectively submitted a comment under the title California Investor 
Owned Utilities (CA IOUs).
    \18\ The Appliance Standards Awareness Project (ASAP) submitted 
a joint comment on behalf of itself, the American Council for an 
Energy Efficient Economy, the Northeast Energy Efficiency 
Partnerships, the Northwest Energy Efficiency Alliance, and the 
Alliance to Save Energy collectively. This comment is referred to as 
``ASAP Joint Stakeholders'' throughout this final rule.
---------------------------------------------------------------------------

    For consumer gas-fired storage water heaters greater than or equal 
to 20 gallons but less than or equal to 55 gallons in the high draw 
pattern, Bradford White recommended the proposed level be decreased by 
0.015. (Bradford White, No. 26 at p. 4) AHRI commented that 16 of the 
62 consumer gas-fired storage water heater basic models tested for this 
rulemaking tested into the high draw pattern had measured UEF values 
below the proposed standard and requested the proposed level be 
decreased by 0.02. (AHRI, No. 27 at p. 2) Rheem commented that 37 of 
the 86 consumer gas-fired storage water heater basic models in the high 
draw pattern in the AHRI Directory convert to below the proposed 
standard and requested the proposed level be decreased by 0.01. (Rheem, 
No. 32 at p. 9) In reviewing its test data for the August 2016 SNOPR, 
DOE has found that 9 of the 61 \19\ models tested had measured UEF 
values below the proposed standard, but that 6 of these 9 models also 
had measured EF values below the existing EF standard. Thus, most 
models with measured EF values at or above the current EF standard had 
measured UEF values at or above the proposed UEF standard. Further, as 
discussed in section III.A, DOE expects certain models that meet the 
current EF standard will not meet the UEF standard when tested. DOE 
accounts for this possibility through applying an enforcement policy to 
certain models, as discussed in section III.E. Further, when DOE 
analyzed converted values for models on the market based on their 
published ratings, as was done by Rheem,\20\ DOE found that for 
consumer gas-fired storage water heaters that would be classified in 
the high draw pattern based on their converted first-hour rating, none 
have converted UEF values below the UEF standard level proposed in the 
August 2016 SNOPR. Thus, DOE concludes an adjustment to the proposed 
UEF standard for consumer gas-fired storage water heaters in the high-
use draw pattern bin is not warranted.
---------------------------------------------------------------------------

    \19\ CS-95 has a measured first-hour rating of 74.6 gallons and 
was tested to the medium draw pattern. If the first-hour rating is 
rounded to the nearest gallon, it would have been tested in the high 
draw pattern.
    \20\ To convert from represented values under the previous 
metrics (i.e., EF, TE, and SL) to represented values under the UEF 
metric, manufacturers should utilize measured values obtained during 
testing under the previous test methods, where those values are 
required in the conversion factor equations. DOE provides an 
analysis of converted values based on published ratings for 
illustrative purposes only, in order to respond to commenters who 
performed analysis based on the rated values.
---------------------------------------------------------------------------

    For consumer gas-fired storage water heaters less than or equal to 
55 gallons in the low-draw-pattern bin, Rheem stated that it found two 
EF-compliant models that would have a converted UEF 0.01 below the 
proposed standard, the data for which was supplied to DOE by AHRI 
during the development of the SNOPR. Further, Rheem stated that the 
SNOPR test data does not include any consumer gas-fired storage water 
heaters with a measured first-hour rating that would place the model in 
the low draw pattern and that it cannot identify these models within 
the tested data. Therefore, Rheem requested the proposed standards be 
decreased by 0.01. (Rheem, No. 32 at p. 9) In examining the August 2016 
SNOPR test data, DOE notes that AHRI supplied test data for the 
consumer gas-fired storage water heaters identified as CS-66, CS-70, 
CS-89, CS-99, and CS-137, for which the application of the NOPR 
conversion factors for first-hour ratings would result in a converted 
first-hour rating that would classify the models in the low-draw-
pattern bin. However, when applying the August 2016 SNOPR conversion 
factors, these models have converted first-hour ratings that would 
classify them in the medium-draw-pattern bin, and no models within the 
entire test data set have a converted first-hour rating that would 
result in testing to the low draw pattern. CS-89 and CS-90 (identified 
by AHRI as models CGS-17 and CGS-18, respectively) were tested to the 
low draw pattern, and AHRI provided those test results in response to 
the NOPR. DOE notes that CS-89 has a measured EF 0.05 above the minimum 
EF and a measured UEF 0.06 above the minimum UEF, while CS-90 has a 
measured EF 0.01 above the minimum EF and a measured UEF 0.01 above the 
minimum UEF. Therefore, DOE has determined that a decrease in the 
efficiency level for consumer gas-fired storage water heaters in the 
low draw pattern is not warranted.
    For consumer electric storage water heaters less than or equal to 
55 gallons in the low draw pattern, Bradford White recommended the 
proposed level be decreased by approximately 0.01 UEF to make the 
associated formula to 0.9160--(0.0003 x Vr). (Bradford 
White, No. 26 at p. 4) For those same water heaters, AHRI commented 
that all 11 basic models that were tested had measured UEF values below 
the proposed standard and requested the proposed standard be decreased 
by 0.01. (AHRI, No. 27 at p. 2) Rheem stated that 21 of the 31 electric 
storage water heaters that would have a converted first-hour rating 
that would classify them in the low draw pattern in the AHRI directory 
have converted UEF values below the proposed UEF standard, and that 
most of those models are around 30 gallons. Rheem requested that either 
the proposed standard be decreased by 0.01 or the slope be adjusted to 
allow the 30 gallon units to pass. (Rheem, No. 32 at pp. 9-10)
    Rheem also commented that under the EF test procedure, electric 
storage water heaters only had to be tested once, and provisions were 
in place to allow multiple wattage configurations to be rated using the 
one test. Under the UEF test procedure, Rheem noted that electric 
storage water heaters now have to test each wattage to the first-hour 
rating test, and if a lower wattage puts the model in a different draw 
bin, the different UEF standard in that lower bin may not be met, 
whereas that configuration complied with the corresponding EF standard. 
Rheem commented that this essentially means the UEF standards for these 
draw patterns are more stringent than the EF standards. (Rheem, No. 32 
at p. 10)
    In examining the August 2016 SNOPR test data, DOE found that 12 of 
the 13 consumer electric storage water heaters with storage volumes 
below 55 gallons that were tested in the low draw pattern had measured 
UEF values below the proposed standard; however, 9 of those 12 models 
also had measured EF values

[[Page 96222]]

below the EF energy conservations standards. This indicates that for 
most models, the relationship between the measured EF and EF standard 
(i.e., whether the measured EF is higher or lower than the standard) 
holds true for UEF as well. In response to Rheem's comment regarding 
testing of electric storage water heaters, DOE acknowledges that more 
testing is required under the UEF test procedure as compared to the EF 
test procedure. DOE notes that the UEF standards in the lower draw 
patterns are less stringent and are based on models with 
characteristics representative of that draw pattern. Thus, they should 
be applicable to electric storage water heaters being tested at lower 
element wattages and avoid the situation that Rheem describes where an 
electric storage water heater is compliant with one heating element 
wattage, but not with another. In addition, DOE reiterates that it 
expects certain models that meet the current EF standard will not meet 
the UEF standard when tested, and accounts for this possibility through 
an enforcement policy for certain models, as discussed in section 
III.E. Based on the foregoing, DOE has determined an adjustment to the 
proposed standard for electric storage water heaters is not warranted.
    For consumer gas-fired instantaneous water heaters less than 2 
gallons, Bradford White, AHRI, and Rheem recommended that the proposed 
level be decreased to those proposed in the April 2015 NOPR (i.e., 0.80 
for all draw patterns). AHRI argued that the actual difference between 
the NOPR and SNOPR levels of 0.003 (0.804 as compared to 0.807) 
resulted in a 0.01 change in the UEF standard level due to rounding. 
AHRI commented further that the converted UEF values for 20 of the 96 
basic models in the AHRI Directory are less than the minimum UEF values 
proposed in the August 2016 SNOPR. Rheem stated that many models, 
specifically those in the low and medium draw pattern, are not meeting 
the proposed standard through the use of the conversion factor. 
(Bradford White, No. 26 at p. 4; AHRI, No. 27 at p. 2; Rheem, No. 32 at 
p. 11) In examining the August 2016 SNOPR test data, DOE found that 5 
of the 53 consumer gas-fired instantaneous water heater models that 
were tested had measured UEF values below the proposed standards; 
however, 4 of the 5 models also had measured EF values below the 
existing EF standards. This indicates that for most models the 
relationship between the measured EF and EF standard (i.e., whether the 
measured EF is higher or lower than the standard) holds true for UEF as 
well. Further, as was done by commenters, DOE also examined the number 
of models that would pass the proposed UEF standard based on their 
converted UEF determined using published values, and found that about 
20 percent of the consumer gas-fired instantaneous water heaters on the 
market would have converted UEF values less than the SNOPR proposed 
standards, and all of the converted values were 0.01 below. All of 
these models were in the medium and high draw pattern bins. As stated 
above, the ``representative model'' method was not derived to ensure 
all models on the market convert to pass the converted standards. 
Rather, some models are expected to fall below the converted UEF 
standards, and these models are accounted for by the enforcement policy 
provisions discussed in section III.E. Therefore, DOE has decided to 
adopt the conversion factors proposed in the August 2016 SNOPR.
    For consumer oil-fired storage water heaters in the high draw 
pattern, AHRI and Bock commented that two Bock 32E oil-fired storage 
water heaters were tested to the EF and UEF test procedures, and the 
average tested UEF value was below the proposed UEF standard. Further, 
the commenters noted that a similar model tested by DOE, identified in 
the August 2016 SNOPR as CS-27, tested below the proposed minimum. 
Therefore, AHRI and Bock requested that the proposed level be decreased 
by 0.02. (AHRI, No. 27 at p. 2; Bock, No. 29 at p. 2) As stated in 
section III.D.2.a, CS-27 is the Bock 32E, so DOE included the two Bock 
supplied test data points by averaging the results with those of CS-27, 
and derived new first-hour rating and UEF conversion factors. These 
conversion factors were carried through the analysis to derive updated 
energy conservation standards. The Bock 32E has a rated storage volume 
of 32 gallons (which DOE assumed would be adjusted to 30 gallons after 
the 5 percent decrease is applied to represent the value based on the 
mean of the measured volumes, and the value is rounded to the nearest 
gallon) and is in the high draw pattern which corresponds to a minimum 
UEF of 0.64. This updated minimum UEF value is equal to the mean of the 
measured UEF values for the Bock 32E that were submitted by Bock. 
Therefore, for the final rule, DOE is adopting the standards derived 
using the test data supplied by Bock.
    For residential-duty commercial gas-fired storage water heaters in 
the high draw pattern, Rheem commented that the proposed standard is 
more stringent than the existing minimum thermal efficiency and maximum 
standby loss standards. Rheem stated that a unit with a storage volume 
of 100 gallons that meets the existing energy conservation standards 
would have a converted UEF that is 0.01 below the proposed UEF 
standard. Therefore, Rheem recommended lowering the proposed standard 
by 0.01. (Rheem, No. 32 at p. 10) In examining the August 2016 SNOPR 
test data, DOE found that 4 of the 5 minimally compliant residential-
duty commercial gas-fired storage water heater models that were tested 
had measured UEF values below the proposed standards; however, 2 of the 
4 models also had measured TE and SL values below and the above the 
existing standards, respectively. This indicates that for most models, 
the relationship between the measured EF and EF standard (i.e., whether 
the measured EF is higher or lower than the standard) holds true for 
UEF as well. Further, as was done by Rheem, DOE examined the minimally 
compliant residential-duty commercial gas-fired water heaters on the 
market by applying the conversions based on rated values, and found 
that fewer than half of the models would have a converted UEF value 
below the proposed UEF standard based on their rated values. As stated 
above, the ``representative model'' method was not intended to ensure 
all models on the market convert to pass the converted standards, and 
existing models that have UEF values below the converted standard could 
be addressed through DOE's enforcement policy, as discussed in section 
III.E. Further, as discussed in III.A, because DOE's goal is to 
maintain the same stringency of the existing standards under EF, SL and 
TE, and because individual models are impacted differentially by the 
change in test method and metric, some models that were previously 
minimally compliant will perform better than the translated UEF 
minimum, and others will perform worse. The possibility of such 
outcomes does not mean that the conversion methodology is improper and, 
based on the results of testing, DOE believes the UEF standard that was 
proposed is equivalent in stringency to the minimum thermal efficiency 
and maximum standby loss standards. Therefore, DOE is adopting the 
conversion factors for residential-duty commercial gas-fired water 
heaters. DOE notes that the residential-duty commercial gas-fired 
conversion factors adopted in this final rule vary slightly \21\

[[Page 96223]]

from those presented in the August 2016 SNOPR. 81 FR 59736, 59798 
(August 30, 2016). To improve the accuracy and maintain consistency 
with other product classes, DOE removed certain individual models, 
which were found to be duplicates (i.e., models with identical designs 
that were listed under different model numbers by manufacturers), from 
the final rule dataset (so as not to give additional weight to models 
sold under various brand names). However, DOE notes that the resultant 
equations are essentially the same as those presented in the August 
2016 SNOPR, and when rounded to the nearest 0.01, do not impact the UEF 
standard level for any models currently available on the market.
---------------------------------------------------------------------------

    \21\ For example, for the high draw pattern for residential-duty 
commercial gas-fired water heaters, the constant in the equation has 
changed from 0.6592 in the August 2016 SNOPR to 0.6597 in this final 
rule, a difference of 0.0005. The coefficient multiplied by the 
volume remains 0.0009, which is the same as proposed in the August 
2016 SNOPR.
---------------------------------------------------------------------------

    For consumer gas-fired storage water heaters below 55 gallons, DOE 
requested comment on whether its tentative decision to use the standard 
and low NOX conversion to derive the proposed standard was 
appropriate, as well as its tentative decision that a separate standard 
for ultra-low NOX water heaters was not necessary. CA IOUs, 
Bradford White, AHRI, A.O. Smith, and Rheem all stated that that there 
should not be separate standards for ultra-low NOX. (CA 
IOUs, No. 25 at p. 3; BWC, No. 26 at p. 6; AHRI, No. 27 at p. 10; A.O. 
Smith, No. 28 at p. 5; Rheem, No. 32 at p. 12) CA IOUs also commented 
that in future rulemakings, ultra-low NOX water heaters 
should continue to be examined separately from standard and low 
NOX water heaters. (CA IOUs, No. 25 at p. 3) Therefore, DOE 
has decided not to create separate standards for ultra-low 
NOX water heaters and will continue use the standard and low 
NOX conversion to derive the converted energy conservation 
standards.
    For consumer gas-fired storage water heaters above 55 gallons, DOE 
requested comment on whether the assumptions it used to create 
representative models were reasonable. Bradford White, AHRI, A.O. 
Smith, and Rheem all stated that the assumptions made in the August 
2016 SNOPR were reasonable. (BWC, No. 26 at p. 6; AHRI, No. 27 at p. 
10; A.O. Smith, No. 28 at p. 5; Rheem, No. 32 at p. 12) Therefore, DOE 
continued to use the assumptions presented in the August 2016 SNOPR for 
this final rule.
    For consumer electric instantaneous water heaters, no minimally-
compliant models are available on the market. DOE sought comment 
regarding whether the assumption of 0.93 recovery efficiency reasonably 
approximated a minimally-compliant model. Rheem stated that the 0.93 
recovery efficiency was reasonable and correct. (Rheem, No. 32 at p. 
12) Therefore, DOE continued to use 0.93 as the assumed recovery 
efficiency for a representative consumer electric instantaneous water 
heater in this final rule. In the August 2016 SNOPR, DOE proposed one 
set of standards for consumer electric instantaneous water heaters with 
storage volumes below 2 gallons and another at or above 2 gallons. 81 
FR 59736, 59781 (August 30, 2016). As discussed in section III.B.1, DOE 
is not adopting UEF conversion factors or converting the energy 
conservation standards to UEF for the water heater listed in Table 
III.1, which include consumer electric instantaneous water heaters with 
storage volumes greater than or equal to 2 gallons. Therefore, DOE has 
updated the consumer electric instantaneous water heater energy 
conservation standards to be based solely on representative units with 
storage volumes less than 2 gallons, and will consider electric 
instantaneous water heaters with storage volumes greater than or equal 
to 2 gallons in a future proceeding.
    For grid-enabled water heaters, AHRI and A.O. Smith commented that 
the proposed minimum energy conservation standard levels are 
acceptable. (AHRI, No. 27 at p. 9; A.O. Smith, No. 28 at p. 5) NRECA 
Joint Stakeholders stated that any establishment of a UEF for grid-
enabled water heaters should await product development, and DOE should 
explicitly state that products meeting the EF energy conservation 
standard in the Energy Efficiency Improvement Act of 2015 (EEIA 2015) 
are compliant. (NRECA Joint Stakeholders, No. 30 at pp. 1-3) Rheem 
asserted that as grid-enabled water heaters have only recently been 
introduced into the market and no test data are available for them, 
they will not be able to use the conversion factor to rate the UEF. 
Further, Rheem argued that it is not reasonable for industry to be 
required to determine UEF values for grid-enabled water heaters by 
testing in accordance with the UEF test procedure, when no testing of 
this class was performed by DOE to establish adequate UEF standards. 
Rheem also argued that DOE should postpone establishing a conversion 
factor and converted UEF standard for grid-enabled water heaters until 
a future rulemaking once more models are available to be tested. 
(Rheem, No. 32 at pp. 4-6) In response, DOE notes that when EEIA 2015 
was enacted, there were no grid-enabled storage water heaters on the 
market. As explained in section III.D.2.d, DOE has concluded that, with 
respect to characteristics that might affect the outcome of the old and 
current test procedures, grid-enabled water heaters are not designed 
and do not function differently than consumer electric storage water 
heaters below 55 gallons. For the one grid-enabled storage water heater 
that has subsequently become available on the market and for which 
published product literature is available, the rated EF value is equal 
to the minimum EF standard (when rounded to the nearest 0.01), and the 
converted UEF value (estimated based on its rated values in the AHRI 
Directory) is equal to the proposed standard. This suggests that the 
conversion factor and proposed standards appropriately reflect the 
operation of grid-enabled water heaters. For these reasons, DOE has 
determined that its conversion of existing EF standards for grid-
enabled water heaters to UEF standards are adequate for use at this 
time.
    As originally stated in the August 2016 SNOPR and noted several 
times previously in this final rule, DOE acknowledges that the test 
data that serves as the basis for the August 2016 SNOPR show that some 
units which previously passed the EF, thermal efficiency, and/or 
standby loss energy conservation standards might fail the proposed UEF 
standards, while other units which previously failed might now pass. As 
discussed in section III.A, DOE recognizes that the conversion factors 
presented cannot perfectly model the behavior of all water heaters, as 
each water heater model will react differently to the changes in the 
test procedure based on the characteristics of that particular model. 
The standards presented in Table III.12 and Table III.13 were derived 
using a method that was intended to reduce the number of units that 
would either be non-compliant under the EF test method and compliant 
under the UEF test method or vice versa, so as to maintain the 
stringency of the updated standard. Nevertheless, to ensure that water 
heaters which previously passed the energy conservation standards under 
the ``old'' metrics (i.e., EF, thermal efficiency, and/or standby loss) 
will continue to comply, pre-existing models that were first 
distributed in commerce prior to July 13, 2015 and that are compliant 
with the energy conservation standards denominated in the old metric 
are eligible to have compliance determined based on the old metric, as 
described below in section III.E, if the design of the model is 
unchanged.

[[Page 96224]]

    DOE restates the standards denominated in terms of uniform energy 
factor, as shown in Table III.12 and Table III.13 by product class and 
draw pattern.

                        Table III.12--Consumer Water Heater Energy Conservation Standards
----------------------------------------------------------------------------------------------------------------
                                         Rated storage volume
            Product class               and input rating  (if         Draw pattern        Uniform energy factor
                                             applicable)
----------------------------------------------------------------------------------------------------------------
Gas-fired Storage Water Heater.......  >= 20 gal and <= 55 gal  Very Small.............  0.3456 - (0.0020 x Vr)
                                                                Low....................  0.5982 - (0.0019 x Vr)
                                                                Medium.................  0.6483 - (0.0017 x Vr)
                                                                High...................  0.6920 - (0.0013 x Vr)
                                       > 55 gal and <= 100 gal  Very Small.............  0.6470 - (0.0006 x Vr)
                                                                Low....................  0.7689 - (0.0005 x Vr)
                                                                Medium.................  0.7897 - (0.0004 x Vr)
                                                                High...................  0.8072 - (0.0003 x Vr)
Oil-fired Storage Water Heater.......  <= 50 gal..............  Very Small.............  0.2509 - (0.0012 x Vr)
                                                                Low....................  0.5330 - (0.0016 x Vr)
                                                                Medium.................  0.6078 - (0.0016 x Vr)
                                                                High...................  0.6815 - (0.0014 x Vr)
Electric Storage Water Heaters.......  >= 20 gal and <= 55 gal  Very Small.............  0.8808 - (0.0008 x Vr)
                                                                Low....................  0.9254 - (0.0003 x Vr)
                                                                Medium.................  0.9307 - (0.0002 x Vr)
                                                                High...................  0.9349 - (0.0001 x Vr)
                                       > 55 gal and <= 120 gal  Very Small.............  1.9236 - (0.0011 x Vr)
                                                                Low....................  2.0440 - (0.0011 x Vr)
                                                                Medium.................  2.1171 - (0.0011 x Vr)
                                                                High...................  2.2418 - (0.0011 x Vr)
Tabletop Water Heater................  >= 20 gal and <= 120...  Very Small.............  0.6323 - (0.0058 x Vr)
                                                                Low....................  0.9188 - (0.0031 x Vr)
                                                                Medium.................  0.9577 - (0.0023 x Vr)
                                                                High...................  0.9884 - (0.0016 x Vr)
Instantaneous Gas-fired Water Heater.  < 2 gal and > 50,000     Very Small.............  0.80
                                        Btu/h.                  Low....................  0.81
                                                                Medium.................  0.81
                                                                High...................  0.81
Instantaneous Electric Water Heater..  < 2 gal................  Very Small.............  0.91
                                                                Low....................  0.91
                                                                Medium.................  0.91
                                                                High...................  0.92
Grid-Enabled Water Heater............  >75 gal................  Very Small.............  1.0136 - (0.0028 x Vr)
                                                                Low....................  0.9984 - (0.0014 x Vr)
                                                                Medium.................  0.9853 - (0.0010 x Vr)
                                                                High...................  0.9720 - (0.0007 x Vr)
----------------------------------------------------------------------------------------------------------------
* Vr is the Rated Storage Volume (in gallons), as determine pursuant to 10 CFR 429.17.


      Table III.13--Residential-Duty Commercial Water Heater Energy
                         Conservation Standards
------------------------------------------------------------------------
                                                        Uniform energy
          Product class              Draw pattern           factor
------------------------------------------------------------------------
Gas-fired Storage...............  Very Small........  0.2674 - (0.0009 x
                                                       Vr)
                                  Low...............  0.5362 - (0.0012 x
                                                       Vr)
                                  Medium............  0.6002 - (0.0011 x
                                                       Vr)
                                  High..............  0.6597 - (0.0009 x
                                                       Vr)
Oil-fired Storage...............  Very Small........  0.2932 - (0.0015 x
                                                       Vr)
                                  Low...............  0.5596 - (0.0018 x
                                                       Vr)
                                  Medium............  0.6194 - (0.0016 x
                                                       Vr)
                                  High..............  0.6740 - (0.0013 x
                                                       Vr)
Electric Instantaneous..........  Very Small........  0.80
                                  Low...............  0.80
                                  Medium............  0.80
                                  High..............  0.80
------------------------------------------------------------------------
* Vr is the Rated Storage Volume (in gallons), as determined pursuant to
  10 CFR 429.44.

Storage Volume Requirements
    In the July 2014 final rule, DOE amended the certification 
requirements for consumer water heaters to specify that the rated 
storage volume of a water heater must be the mean of the storage 
volumes measured over the sample of tested units. DOE also added 
enforcement provisions that state that if the rated storage volume is 
within 5 percent of the mean of the measured values of storage volume, 
then that rated value will be used as the basis for calculation of the 
required uniform energy factor for the basic model; otherwise, the mean 
of the measured storage volume values will be used as the basis for 
calculation of the required

[[Page 96225]]

uniform energy factor for the basic model. 79 FR 40542, 40565-40566 
(July 11, 2014).
    In the August 2016 SNOPR, DOE proposed to decrease the 5 percent 
tolerance to 2 percent of the mean of the measured value of storage 
volume. 81 FR 59736, 59786 (August 30, 2016). As discussed in the 
August 2016 SNOPR, based on testing performed on a sample of 24 units, 
DOE observed that a tolerance of 2 percent more accurately reflects the 
actual level of variability that manufacturers are currently able to 
achieve and allows for slightly more variability than what was observed 
in the sample set. Id.
    Bradford White, AHRI, Rheem, and Giant Factories, Inc. (Giant) 
commented that they are opposed to the decrease in storage volume 
tolerance from 5 percent to 2 percent. Bradford 
White and AHRI also argued that the sample size used as the basis for 
the new requirements was too small and not statistically sound. 
(Bradford White, No. 26 at p. 3; AHRI, No. 27 at p. 4; Rheem, No. 32 at 
p. 8; Giant, No. 33 at p. 2) Bradford White and Rheem alleged that DOE 
did not consider the manufacturing costs associated with controlling 
tank volume variability. (Bradford White, No. 26 at p. 3; Rheem, No. 32 
at p. 8) Rheem also stated that the costs of this change could amount 
to hundreds of thousands of dollars. (Rheem, No. 32 at p. 6) Giant and 
Rheem commented that because the rated volume is part of the water 
heater safety certification, any change in the rated storage volume 
would require a manufacturer to update its safety certification reports 
and perform validation testing at a cost that is not negligible. 
(Rheem, No. 32 at pp. 7-8; Giant, No. 33 at p. 2) Rheem requested 
clarification as to whether manufacturers will be permitted to 
advertise a different ANSI/UL 174 rated volume than the DOE UEF test 
procedure rated volume. (Rheem, No. 32 at pp. 7-8) Bradford White, 
AHRI, and Rheem argued that the requirement to round to the nearest 
gallon uses up some of the 2 percent tolerance and causes the tolerance 
to become more stringent than 2 percent. For smaller gallon sizes, the 
commenters asserted this results in almost no tolerance.\22\ (Bradford 
White, No. 26 at p. 3; AHRI, No. 27 at p. 4; Rheem, No. 32 at pp. 7-10) 
AHRI requested clarification of the exact consequences of measuring a 
volume that is beyond 2 percent of the rated volume during a test with 
a passing measured UEF, particularly if the measured volume places the 
water heater into a different product category such as not a grid-
enabled or above 55 gallons. (AHRI, No. 27 at p. 5) A.O. Smith also 
urged DOE to provide further clarification regarding any potential 
liability that a manufacturer may incur if the measured volume during 
an enforcement test is more than 2 percent outside the newly defined 
DOE rated volume, and if there is any further consequence beyond that 
the measured volume will be used for the enforcement test and to 
determine the minimum efficiency. (A.O. Smith, No. 28 at p. 2) Giant 
stated that for products such as grid-enabled water heaters, a model 
with a measured volume of 70 gallons and a rated volume of 76 gallon 
model would now have a maximum rated volume of 71.4 gallons and no 
longer meet the definition of a grid-enabled water heater. (Giant, No. 
33 at p. 2) Bradford White and Giant commented that reducing the 
tolerance to 2 percent could result in an increase in energy use as 
manufacturers redesign their products to increase the tank size to a 
nominal value, adding that this change would lead to significant 
confusion in the market. (Bradford White, No. 26 at p. 3; Giant, No. 33 
at pp. 2; Rheem, No. 32 at pp. 7-10)
---------------------------------------------------------------------------

    \22\ AHRI cited an example of a water heater with 27.5 gallons 
of measured storage volume. The rated storage volume would be 
rounded to 28 gallons, and the 0.5 gallon difference would represent 
a 1.8 percent deviation from the rated volume.
---------------------------------------------------------------------------

    After considering the comments, DOE performed a statistical 
analysis based on a t-distribution rather than a normal distribution as 
was done for the August 2016 SNOPR, which DOE concluded to be more 
appropriate for the number of samples available. For each model, DOE 
calculated the t-based 95-percent confidence interval, which 
corresponds to the maximum amount of deviation from the mean one would 
expect if a new sample were tested. DOE found a maximum percent 
deviation from the mean of three percent using this method; therefore, 
DOE is adopting a three-percent tolerance on measured storage volume 
instead of the proposed two percent. The three-percent tolerance more 
accurately reflects the level of variability that manufacturers are 
currently able to achieve. In addition, if manufacturers do not certify 
the rated storage volume in accordance with the requirements of 10 CFR 
429.17 (i.e., as the mean of the measured storage volume of the 
sample), the certified value may be considered invalid which could lead 
to DOE investigating the data underlying the certification in 
accordance with 10 CFR 429. With regard to the manufacturing costs 
associated with controlling tank volume variability, DOE notes that its 
test data show that manufacturers already control tank volume 
variability within the bounds being adopted, and thus, additional costs 
are not expected as manufacturers already appear to have this 
capability. Regarding potential increased energy usage, DOE 
acknowledges that a redesign of the tank size to a nominal value is 
possible. If the redesigned tank is larger than the previous tank, then 
it would likely use slightly more energy. DOE also acknowledges that 
there may be costs associated with safety certification of a re-
designed model. However, DOE notes that the requirement that the rated 
volume be the mean the measured volumes in the test sample already 
exists at 10 CFR 429.17(a)(1)(ii)(C), and this change only modifies the 
existing tolerance in response to comments. Thus, the rated efficiency 
should already be equal to the mean the measured volumes in the test 
sample, and as discussed above, DOE's data show that manufacturers 
already control their volume within this tolerance. Finally, in 
response to Giant's comments that certain products that have a volume 
threshold, such as grid-enabled water heaters, may need to be 
reclassified based on the new storage volume requirements, that is 
correct. However, DOE contends that if the manufacturer was properly 
certifying to the July 2014 test procedure, there would be no 
reclassification needed.

E. Enforcement Policy

    In the August 2016 SNOPR, DOE acknowledged that the nature of the 
conversion process could conceivably result in models very close to the 
standard falling below the converted standard. Recognizing that there 
is value in reducing the uncertainty for manufacturers and that there 
is no significant public harm in letting manufacturers continue sales 
of certain models, DOE explained its planned approach for basic models 
where units of individual models within the basic model were 
manufactured prior to July 13, 2015. 81 FR 59736, 59876-59787 (August 
30, 2016). Specifically, DOE explained that in assessment and 
enforcement testing, DOE will evaluate the compliance of a basic model 
using the test procedure in effect prior to July 13, 2015, under the 
following circumstance: The basic model must have been in distribution 
in commerce prior to July 13, 2015; the basic model must have been 
tested and properly certified to DOE as compliant with the applicable 
standard prior to July 13, 2015; and the units manufactured prior to 
July 13, 2015, must be essentially

[[Page 96226]]

identical to the units manufactured on or after July 13, 2015.\23\
---------------------------------------------------------------------------

    \23\ The last requirement for this policy--that units must be 
essentially identical--bears explanation. DOE generally permits 
manufacturers great latitude in assigning basic model numbers, and 
manufacturers normally are not required to certify a model as a new 
basic model if modifications make the model more efficient. In the 
August 2016 SNOPR, DOE stated that, if a manufacturer makes changes 
to a model (that make it either more efficient or less), then it 
should conduct the requisite testing using the UEF test procedure 
and ensure the compliance of the model with the converted standard. 
The proposed policy was intended to give certainty to manufacturers 
with respect to historical models; it was not intended to provide a 
mechanism to perpetuate an obsolete test method and obsolete 
metrics.
---------------------------------------------------------------------------

    In the August 2016 SNOPR, DOE also recognized that manufacturers 
seek certainty that models introduced (i.e., first distributed in 
commerce) on or after July 13, 2015, will not be subject to civil 
penalties. In enforcing the standard(s) for models introduced on or 
after July 13, 2015, and before the effective date of this final rule, 
DOE stated that it would consider whether these models meet the 
standard(s) as denoted using the ``old'' metric(s), the deviation from 
the UEF standard when tested using the UEF test procedure, and efforts 
taken by the manufacturer to ensure compliance with the converted UEF 
standards. 81 FR 59736, 59787 (August 30, 2016).
    In response to the number of comments and questions DOE received in 
response to its enforcement policy as presented in the August 2016 
SNOPR, DOE is explaining its enforcement policy in greater detail in 
this final rule, as well as offering minor clarifications in response 
to comments.
    In the event that DOE selects a model for assessment testing that 
was first distributed in commerce prior to July 13, 2015, DOE will 
first assess compliance with the UEF standard. If testing indicates 
that an individual model is noncompliant with the UEF standard, DOE 
will then evaluate compliance using the ``old'' metrics (i.e., EF or 
thermal efficiency/standby loss, as applicable). DOE may request that 
the manufacturer provide information to show that the selected model 
met the minimum efficiency standard using the test procedure in effect 
prior to July 13, 2015, and that it has not been redesigned since that 
time. (DOE discusses the issue of whether a model has been redesigned 
later within this section.) The model will continue to be subject to 
the enforcement policy as long as all units of that model manufactured 
remain identical \24\ to the units of that model that were being 
manufactured prior to July 13, 2015. These models will continue to 
remain subject to the enforcement policy until compliance with amended 
energy conservation standards is required.
---------------------------------------------------------------------------

    \24\ DOE acknowledges that in the August 2016 SNOPR it used the 
term ``essentially identical'' to refer to the similarities between 
units manufactured prior to July 13, 2015, and units manufactured on 
or after that date, one factor relevant to application of the 
enforcement policy set forth here. DOE realizes that, due to that 
term's presence in the definition of ``basic model'' at 10 CFR 
430.2, including this term in its statement of enforcement policy 
may cause confusion, particularly given DOE's application of the 
enforcement policy on an individual model basis. Thus, DOE is 
adopting the use of the term identical in this final enforcement 
policy and has included additional explanation to help manufacturers 
understand how it applies.
---------------------------------------------------------------------------

    To address any confusion regarding this enforcement policy, the 
policy will apply to individual models, rather than basic models. DOE 
generally permits manufacturers great latitude in assigning basic model 
numbers, and manufacturers normally are not required to certify a model 
as a new basic model if modifications make the model more efficient. 
However, in implementing this policy, DOE believes that if a 
manufacturer makes changes to the design of an individual model, then 
DOE would no longer consider the individual model ``identical'' to the 
units manufactured prior to July 13, 2015, and the model would not be 
subject to the enforcement policy. In such a case, the manufacturer 
should conduct the requisite testing using the UEF test procedure and 
ensure the compliance of the model with the converted standard. 
Further, if a manufacturer groups, within the same basic model, an 
individual model subject to DOE's enforcement policy with one or more 
individual models not subject to the policy, DOE would not treat the 
individual model as subject to the policy. Thus, if certain individual 
models within a basic model are redesigned, those individual models 
would have to be recertified as a separate basic model (or basic 
models) from the original basic model.
    A.O. Smith requested clarification as to what is meant by the 
requirement that units for ``grandfathered'' models must be essentially 
identical to those manufactured prior to July 13, 2015, as DOE proposed 
in the August 2016 SNOPR. (A.O. Smith, No. 28 at p. 4) Rheem also 
sought clarification regarding what will be considered sufficient 
evidence to demonstrate a ``grandfathered'' model met the provisions 
laid out by DOE. (Rheem, No. 32 at p. 16)
    Regarding the term ``essentially identical'' used in the August 
2016 SNOPR, as well as the term ``identical'' used in this final rule 
and intended to have the same meaning, units of models that were 
manufactured after July 13, 2015, must have the same design as those 
manufactured before July 13, 2015, to be subject to the enforcement 
policy described above. If an individual model is redesigned in any 
way, it would no longer be subject to the policy. However, DOE 
recognizes that manufacturers may need to make small changes, such as a 
change in component supplier, that do not change the design and, thus, 
would not constitute a different ``design'' from the units of that 
model that were manufactured prior to July 13, 2015. One example of 
such a change would be a change in foam suppliers, where the properties 
of the foam were the same. Such changes would not be considered as a 
re-design of the model as long as the new component is identical to the 
component it replaces in the original model. In such instances, DOE 
would consider the design identical to that of the original model, and 
units of that model would be subject to the enforcement policy provided 
they, at a minimum, meet the energy conservation standards in place 
under the ``old'' metrics (i.e., energy factor, thermal efficiency, and 
standby loss). DOE understands that manufacturers typically change 
suppliers of components or source raw materials (e.g., foam or metals) 
as part of their day-to-day operations, and DOE does not consider 
sourcing decisions for the same components to constitute a non-
identical model. In contrast, if a manufacturer were to redesign the 
product by introducing a new burner design for a gas water heater or by 
changing the formulation of the foam for a storage-type water heater, 
DOE would consider these changes as redesigns because such changes 
affect the performance and operation of the model. In these instances, 
a manufacturer should: (1) Arrive at represented values expressed in 
UEF in accordance with the test procedure and the amendments in this 
final rule; (2) ensure that the redesigned individual model complies 
with the applicable UEF standard; and (3) properly certify the 
individual model before distribution in commerce (either as its own 
basic model or as part of a basic model that does not have any other 
individual models which are subject to the enforcement policy). As part 
of considering whether units of an individual model were identical, DOE 
would consider a manufacturer's records of the bills of materials for 
models initially distributed in commerce before July 13, 2015, and for

[[Page 96227]]

which they wish to demonstrate compliance based on the ``old'' metrics 
that show all components in the model prior to July 13, 2015. Such 
evidence would aid DOE in assessing whether units manufactured after 
July 13, 2015, remain identical to those manufactured prior to that 
date.
    Bradford White requested clarification as to whether updating a 
product's rated volume would void ``grandfathering'' of a model that 
was introduced prior to July 13, 2015, assuming the other conditions 
DOE has laid out are met. (Bradford White, No. 26 at p. 2) As stated 
above, a model will not be eligible for DOE's enforcement policy if 
there was any design change. A change in the rated volume would not be 
a change in the design of the products themselves in that sense; it 
would be a change only in representations about the products. However, 
if rather than simply changing the rated value, the manufacturer 
chooses to redesign the model with a different volume such that the 
design would not be identical, such a model would not be subject to the 
policy.
    The ASAP Joint Stakeholders noted that the water heater industry 
has called for explicit grandfathering of water heaters that comply 
with minimum efficiency standards when expressed in terms of EF, but 
not in terms of UEF, and argued that AEMTCA does not provide for such 
grandfathering. ASAP Joint Stakeholders' also expressed their 
understanding of the proposed grandfathering provisions as allowing EF-
compliant water heaters to be sold for a year following the publication 
of the final rule, after which DOE would not enforce the UEF standards 
for an unlimited period of time for essentially identical, but UEF non-
compliant, models. The ASAP Joint Stakeholders commented that adopting 
non-enforcement as a tool for energy efficiency standards 
implementation would set a terrible precedent, would create the need 
for DOE to continually monitor UEF non-compliant models, and would 
create uncertainty for industry and uncertainty about the ultimate 
impacts of the water heater efficiency standards. (ASAP Joint 
Stakeholders, No. 31 at p. 4)
    To be clear, this enforcement policy is not ``grandfathering''--DOE 
is not allowing manufacture of products that do not meet a standard. As 
discussed above, the conversion factor can, for some models, change the 
compliance status as a result of changes in the test method; this 
enforcement policy ensures that a model that complied with the former 
metrics is not harmed by the transition to UEF. However, as soon as a 
manufacturer makes any change to a model, the manufacturer must test 
and ensure compliance with the new metric. This enforcement policy 
allows a smooth transition through a metric change but does not allow 
manufacture of non-compliant products. Moreover, this is not a policy 
of non-enforcement--DOE is adopting a policy of conducting additional 
testing, where needed, for a limited subset of models in order to 
assess compliance using a second metric. DOE emphasizes that only 
models manufactured and certified prior to July 13, 2015, are eligible 
for the full enforcement policy; therefore, DOE has a known, finite 
list of models eligible for this relief.
    With respect to the ``transition'' models first distributed in 
commerce between July 13, 2015, and the publication date of this rule, 
DOE has committed to consider compliance using the former test method 
as a factor only and expects manufacturers to take appropriate, timely 
steps to ensure those models meet the standard as measured using the 
UEF test method--which was the applicable test method at the time of 
manufacture. Further, because DOE is not permitting manufacturers to 
``overrate'' to the minimum UEF standard, manufacturers are required to 
disclose the actual performance in the same metric as all other 
products.

F. Certification

    In this final rule, DOE adopts its position as stated in the August 
2016 SNOPR, that upon the effective date of this final rule, 
certification of compliance with energy conservation standards will be 
exclusively in terms of UEF. 81 FR 59736, 59788 (August 30, 2016). In 
implementing the provisions of 42 U.S.C. 6295(e)(5), DOE has concluded 
that there will be three possible paths available to manufacturers for 
certifying compliance of basic models of consumer water heaters that 
were certified before July 13, 2015: (1) In the year following the 
publication of this final rule, convert the energy factor values 
obtained using the test procedure contained in appendix E to subpart B 
of 10 CFR part 430 of the January 1, 2015 edition of the CFR from 
energy factor to uniform energy factor using the applicable 
mathematical conversion factor, and then use the converted uniform 
energy factors along with the applicable sampling provisions in 10 CFR 
part 429 to determine the represented uniform energy factor; or (2) 
conduct testing using the test procedure contained at appendix E to 
subpart B of 10 CFR part 430, effective July 13, 2015, along with the 
applicable sampling provisions in 10 CFR part 429; or (3) where 
permitted, apply an alternative efficiency determination method (AEDM) 
pursuant to 10 CFR 429.70 to determine the represented efficiency of 
basic models for those categories of consumer water heaters where the 
``tested basic model'' was tested using the test procedure contained at 
appendix E to subpart B of 10 CFR part 430, effective July 13, 2015.
    Similarly, DOE has concluded that there will be three possible 
paths available to manufacturers for certifying compliance of basic 
models of commercial residential-duty water heaters that were certified 
before July 13, 2015: (1) In the year following the publication of this 
final rule, convert the thermal efficiency and standby loss values 
obtained using the test procedure contained in 10 CFR 431.106 of the 
January 1, 2015 edition of the CFR from thermal efficiency and standby 
loss to uniform energy factor using the applicable mathematical 
conversion factor, and then use the converted uniform energy factors 
along with the applicable sampling provision in 10 CFR part 429 to 
determine the represented uniform energy factor; or (2) conduct testing 
using the test procedure at 10 CFR 431.106, effective July 13, 2015, 
along with the applicable sampling provisions in part 429; or (3) where 
permitted, apply an alternative efficiency determination method (AEDM) 
pursuant to 10 CFR 429.70 to determine the represented efficiency of 
basic models for those categories of commercial water heaters where the 
``tested basic model'' was tested using the test procedure at 10 CFR 
431.106, effective July 13, 2015.
    Bradford White, AHRI, Rheem, and Giant commented that it would take 
at least 6 months after the publication of this final rule to convert 
efficiency and performance ratings to those under the UEF test method. 
(Bradford White, No. 26 at p. 5; AHRI, No. 27 at p. 5; Rheem, No. 32 at 
pp. 14-15; Giant, No. 33 at p. 2) AHRI, Rheem, and Giant further stated 
that the FTC EnergyGuide compliance date is June 12, 2017, and if this 
final rule is delayed past December 12, 2016, DOE and FTC should 
coordinate actions to delay the effective date of the revised FTC label 
so as to maintain the 6-month period. AHRI, Rheem, and Giant added that 
because the next annual certification date is May 1, 2017, DOE should 
delay the annual certification requirement until the effective date of 
the FTC EnergyGuide label, due to the potential for confusion resulting 
from different values in certification data in the DOE compliance 
certification database and EnergyGuide labels on products. (AHRI,

[[Page 96228]]

No. 27 at p. 5; Rheem, No. 32 at pp. 14-15; Giant, No. 33 at p. 2) A.O. 
Smith stated the next annual certification date should be delayed to 
the expiration date of the conversion factor rulemaking. (A.O. Smith, 
No. 28 at p. 4)
    DOE recognizes stakeholder concerns related to the timing of the 
FTC requirements and certification reports, and the Department agrees 
that harmonizing the dates for submitting certification reports and 
complying with the EnergyGuide labels is desirable to prevent consumer 
confusion and reduce burden on manufacturers. DOE has already issued an 
enforcement policy with respect to certification of water heaters 
subject to this rule. In that policy, DOE stated that the policy would 
be amended when this rule was finalized. DOE hereby revises that policy 
such that DOE will not seek civil penalties for failure to submit a UEF 
certification report, prior to June 12, 2017, for any basic model of 
water heater subject to this final rule. DOE may seek civil penalties 
for failure to submit a UEF certification report for each basic model 
of water heater subject to this final rule starting June 12, 2017.
    Thus, while manufactures are required to submit certifications by 
the May 1, 2017 annual deadline for existing basic models of consumer 
water heaters, as set forth at 10 CFR 429.12(d), DOE will not seek 
civil penalties for failure to submit required certifications by this 
deadline. However, if a manufacturer does not submit its annual 
certification report for each basic model by June 12, 2017, it will be 
subject to civil penalties that will begin accruing on a per day per 
basic model basis as of that date.
    This enforcement policy will not apply to basic models first 
distributed in commerce on or after the publication date of this rule. 
Manufacturers of any such basic model must certify the compliance of 
the basic model before distribution in commerce of the basic model, as 
required by 10 CFR 429.12(a), or be subject to civil penalties for 
failure to do so.
    Rheem also made several comments specifically related to content of 
the FTC EnergyGuide label. (Rheem, No. 32 at pp. 12-14) As noted in 
section I, FTC published a final rule on September 15, 2016 updating 
the EnergyGuide label to reflect changes to the DOE test procedure. 81 
FR 63634. DOE notes that it has no authority to make changes the FTC 
EnergyGuide label; however, DOE has passed Rheem's comments to FTC for 
consideration in future updates to the EnergyGuide label for water 
heaters.
    Rheem stated it is unclear when DOE will transition the ability of 
its compliance certification database to collect the UEF metric rather 
than EF, thermal efficiency, and/or standby loss. AHRI and Rheem 
requested that data be identified as either converted or tested in the 
reporting template to ensure that enforcement testing is not conducted 
based on converted ratings. (AHRI, No. 27 at p. 6; Rheem, No. 32 at p. 
15) AHRI also requested DOE to make a pronouncement that enforcement 
testing will be conducted using the test procedure which was used to 
establish the model's ratings. (AHRI, No. 27 at p. 5) Finally, AHRI 
commented that there should be no risk of a false-positive enforcement 
action based on converted ratings once the conversion factor expires. 
That is, if a model converted into one draw pattern and tested into 
another, enforcement action should be based on the tested ratings and 
energy conservation standards associated with the tested draw pattern. 
(AHRI, No. 27 at p. 6)
    DOE will transition the ability of its compliance certification 
database to collect UEF metrics prior to the date by which 
manufacturers must submit certification reports (i.e., June 12, 2017, 
as discussed previously in this section). The information required for 
certification for the various types of water heaters and methods for 
determining UEF (i.e., based on testing or based on converted values) 
is detailed in the regulatory text at the end of this final rule and 
will appear in 10 CFR part 429 once this final rule is effective. Thus, 
manufacturers will be aware of the certification information that DOE 
will collect. DOE proposed specific data elements based on whether a 
certification was based on converted or tested values, and AHRI and 
Rheem requested that data be identified as either converted or tested 
in the reporting template. Although whether a value was converted or 
tested would be implicit based on the information provided, DOE will, 
as suggested by AHRI and Rheem, explicitly require manufacturers to 
report how the certified values were determined. DOE will also permit 
manufacturers to provide at their option a declaration of whether they 
are requesting that the enforcement policy apply to a basic model, in 
which case the manufacturer must also provide the certified value for 
that model using the old metric(s) and corresponding test data.
    Bradford White requested that DOE provide guidance on how to 
translate back to the ``old'' metrics, so that utility rebate programs 
and codes may have time to transition to the ``new'' metrics. (Bradford 
White, No. 26 at p. 5) In response, DOE shares Bradford White's concern 
about utility rebate programs. However, DOE believes that facilitating 
calculation back to the old metrics for use in utility rebate programs 
would simply prolong the transition to the new metrics and could 
possibly result in consumer confusion regarding water heater efficiency 
ratings. Accordingly, DOE is not adopting the commenter's suggestion.
    In the August 2016 SNOPR, DOE requested comment about its decision 
not to include standby heat loss coefficient (UA), Annual Energy 
Consumption (Eannual), Annual Electrical Energy Consumption 
(Eannual,e), and Annual Fossil Fuel Energy Consumption 
(Eannual,f) in the parameters manufacturers are required to 
certify to DOE. 81 FR 59736, 59787 (August 30, 2016). In response, 
Bradford White, AHRI, and A.O. Smith commented that they supported 
DOE's decision not to include these parameters in the annual 
certification report. (Bradford White, No. 26 at p. 3; AHRI, No. 27 at 
p. 10; A.O. Smith, No. 28 at p. 5) Bradford White stated that 
certifying the additional parameters could increase burden due to 
additional paperwork, while A.O. Smith argued that the additional 
parameters could result in consumer confusion. AHRI stated that the 
values are not necessary for establishing compliance with DOE 
efficiency regulations and the information is not necessary for 
consumers to be able to compare the efficiency of models. CA IOUs 
requested that recovery efficiency continue to be included in the CCMS 
directory. (CA IOUs, No. 25 at p. 2) Having considered these comments, 
DOE will not require the certification of standby heat loss coefficient 
(UA), Annual Energy Consumption (Eannual), Annual Electrical 
Energy Consumption (Eannual,e), and Annual Fossil Fuel 
Energy Consumption (Eannual,f), as these values are not 
necessary for establishing compliance with DOE efficiency regulations 
and requiring reporting of them could unnecessarily create additional 
burden for manufacturers. However, as requested by the CA IOUs, DOE 
will continue to require manufacturers to report recovery efficiency in 
their annual certification reports. Manufacturers are currently 
required to certify the recovery efficiency (see 10 CFR 429.17(b)(2)), 
so maintaining this requirement would not create additional burden, nor 
does is DOE aware of any consumer confusion resulting from the 
inclusion of this specific parameter.
    AHRI, A.O. Smith, and Rheem provided their understanding of how 
``grandfathered'' models will be handled

[[Page 96229]]

and requested that DOE confirm that it is correct. (AHRI, No. 27 at pp. 
6-7; A.O. Smith, No. 28 at pp. 3-4; Rheem, No. 32 at p. 16)
    In response, DOE reiterates that the statute did not grandfather 
any models. With respect to models that do not meet the UEF standard 
when converted or tested using the UEF test procedure, manufacturers of 
models certified prior to July 13, 2015, may continue to certify 
compliance on the basis of the then-applicable test procedure but must 
disclose the UEF rating as discussed above. Manufacturers should not 
represent the efficiency at the minimum UEF standard for models that, 
when rated in accordance with 10 CFR 429.17, would have a UEF rating 
below the minimum standard.

G. Effective Date

    This rule will be effective upon its publication in the Federal 
Register. Ordinarily, pursuant to 5 U.S.C. 553, a rule can only be 
effective 30 days after publication. (This rule is not a major rule to 
which the effective-date delay in 5 U.S.C. 801 would apply.) However, 
DOE finds good cause to make the rule effective immediately. EPCA 
specifies that manufacturers may use the conversion factors established 
by this rule ``beginning on the date of publication of the conversion 
factor in the Federal Register.'' 42 U.S.C. 6295(e)(5)(E)(v)(I). 
Complying with that statutory mandate would require that DOE make the 
rule effective immediately; DOE accordingly finds good cause, under 5 
U.S.C. 553(d)(3), to do so.

IV. Procedural Issues and Regulatory Review

A. Review Under Executive Order 12866

    The Office of Management and Budget (OMB) has determined that test 
procedure rulemakings do not constitute ``significant regulatory 
actions'' under section 3(f) of Executive Order 12866, ``Regulatory 
Planning and Review,'' 58 FR 51735 (Oct. 4, 1993). Accordingly, this 
action was not subject to review under the Executive Order by the 
Office of Information and Regulatory Affairs (OIRA) in the Office of 
Management and Budget.

B. Review Under the Regulatory Flexibility Act

    The Regulatory Flexibility Act (5 U.S.C. 601 et seq., as amended by 
the Small Business Regulatory Enforcement Fairness Act of 1996) 
requires preparation of an initial regulatory flexibility analysis 
(IRFA) for any rule that by law must be proposed for public comment and 
a final regulatory flexibility analysis (FRFA) for any such rule that 
an agency adopts as a final rule, unless the agency certifies that the 
rule, if promulgated, will not have a significant economic impact on a 
substantial number of small entities.
    A regulatory flexibility analysis examines the impact of the rule 
on small entities and considers alternative ways of reducing negative 
effects. Also, as required by Executive Order 13272, ``Proper 
Consideration of Small Entities in Agency Rulemaking,'' 67 FR 53461 
(August 16, 2002), DOE published procedures and policies on February 
19, 2003, to ensure that the potential impacts of its rules on small 
entities are properly considered during the DOE rulemaking process. 68 
FR 7990. DOE has made its procedures and policies available on the 
Office of the General Counsel's Web site at: http://energy.gov/gc/office-general-counsel.
    This final rule prescribes a mathematical conversion that can be 
used on a limited basis to determine the represented values for 
consumer water heaters and certain commercial water heaters. For 
consumer water heaters and certain commercial water heaters, the 
mathematical conversion establishes a bridge between the rated values 
based on the results under the energy factor, thermal efficiency, and 
standby loss test procedures (as applicable) and the uniform energy 
factor test procedure. DOE reviewed this final rule under the 
provisions of the Regulatory Flexibility Act and the policies and 
procedures published on February 19, 2003. 68 FR 7990.
    For the manufacturers of the covered water heater products, the 
Small Business Administration (SBA) has set a size threshold, which 
defines those entities classified as ``small businesses'' for the 
purposes of the statute. DOE used the SBA's small business size 
standards to determine whether any small entities would be subject to 
the requirements of the rule. 65 FR 30836, 30849 (May 15, 2000), as 
amended at 65 FR 53533, 53545 (Sept. 5, 2000), at 77 FR 49991, 50008-
50011 (August 20, 2012), and at 81 FR 4469, 4490 (Jan. 26, 2016), and 
codified at 13 CFR part 121. The size standards are listed by North 
American Industry Classification System (NAICS) code and industry 
description and are available at https://www.sba.gov/sites/default/files/files/Size_Standards_Table.pdf. Consumer water heater 
manufacturing is classified under NAICS code 335228--``Other Major 
Household Appliance Manufacturing.'' The SBA sets a threshold of 1,000 
employees or less for an entity to be considered as a small business 
under that code number. Commercial water heater manufacturing is 
classified under NAICS code 333318--``Other Commercial and Service 
Industry Machinery Manufacturing,'' for which SBA sets a size threshold 
of 1,000 employees or fewer as being considered a small business.
    DOE has identified 11 manufacturers of consumer water heaters that 
can be considered small businesses. DOE identified five manufacturers 
of ``residential-duty'' commercial water heaters that can be considered 
small businesses. Four of the ``residential-duty'' commercial water 
heater manufacturers also manufacture consumer water heaters, so the 
total number of small water heater manufacturers impacted by this rule 
would be 12. DOE's research involved reviewing several industry trade 
association membership directories (e.g., AHRI), product databases 
(e.g., DOE Compliance Certification Database, AHRI, CEC, and ENERGY 
STAR databases), individual company Web sites, and marketing research 
tools (e.g., Hoovers reports) to create a list of all domestic small 
business manufacturers of products covered by this rulemaking.
    For the reasons explained below, DOE has concluded that the test 
procedure amendments contained in this final rule will not have a 
significant economic impact on any manufacturer, including small 
manufacturers.
    For consumer water heaters that were covered under the energy 
factor test procedure and energy conservation standards, the conversion 
factor in this final rule converts the rated values based on the energy 
factor test procedure to values based on the uniform energy factor test 
procedure. Likewise, for certain commercial water heaters, defined 
under the term ``residential-duty commercial water heater,'' the 
conversion factor in this final rule converts the rated values based on 
the previous test procedure to the uniform descriptor which is based on 
the UEF test procedure. The energy conservation standards for 
commercial water heating equipment is denominated using the uniform 
descriptor.
    The conversion factors established in this final rule accomplish 
two tasks: (1) Translating the EF-, TE-, and SL-denominated (as 
applicable) energy conservation standards for consumer water heaters 
and certain commercial water heaters to being expressed in terms of the 
metric and test procedure for uniform energy factor; and (2) providing 
a limited conversion factor that manufacturers can use to translate

[[Page 96230]]

represented values established for basic models certified prior to July 
13, 2015. This limited conversion is a burden-reducing measure which 
helps to ease the transition of the market to the new test procedure 
and uniform metric over the one-year period instead of the typical 180-
day timeframe allotted by statute. In addition, as discussed in section 
III.E, DOE will implement an enforcement policy that DOE will not seek 
civil penalties for the continued manufacture and distribution in 
commerce of units of certain basic models that meet certain conditions 
(as described in III.E), thereby further reducing any burden on small 
business manufacturers. Accordingly, DOE concludes and certifies that 
this rule will not have a significant economic impact on a substantial 
number of small entities, so DOE has not prepared a regulatory 
flexibility analysis for this rulemaking. DOE has provided its 
certification and supporting statement of factual basis to the Chief 
Counsel for Advocacy of the SBA for review under 5 U.S.C. 605(b).

C. Review Under the Paperwork Reduction Act of 1995

    Manufacturers of water heaters must certify to DOE that their 
products comply with any applicable energy conservation standards. In 
certifying compliance, manufacturers must test their products according 
to the DOE test procedures for water heaters, including any amendments 
adopted for those test procedures. DOE has established regulations for 
the certification and recordkeeping requirements for all covered 
consumer products and commercial equipment, including consumer and 
commercial water heaters. 76 FR 12422 (March 7, 2011); 79 FR 25486 (May 
5, 2014). The collection-of-information requirement for the 
certification and recordkeeping is subject to review and approval by 
OMB under the Paperwork Reduction Act (PRA). This requirement was 
approved by OMB under OMB control number 1910-1400, and this 
conversion-factor rule does not constitute a significant change to the 
requirement. Public reporting burden for the certification is estimated 
to average 30 hours per response, including the time for reviewing 
instructions, searching existing data sources, gathering and 
maintaining the data needed, and completing and reviewing the 
collection of information.
    Notwithstanding any other provision of the law, no person is 
required to respond to, nor shall any person be subject to a penalty 
for failure to comply with, a collection of information subject to the 
requirements of the PRA, unless that collection of information displays 
a currently valid OMB Control Number.

D. Review Under the National Environmental Policy Act of 1969

    In this final rule, DOE establishes conversion factors to convert 
results from prior efficiency and delivery capacity metrics (and 
related energy conservation standard requirements) for consumer and 
certain commercial water heaters to the uniform efficiency descriptor. 
DOE has determined that this rule falls into a class of actions that 
are categorically excluded from review under the National Environmental 
Policy Act of 1969 (42 U.S.C. 4321 et seq.) and DOE's implementing 
regulations at 10 CFR part 1021. Specifically, this final rule amends 
the existing rule without affecting the amount, quality, or 
distribution of energy usage, and, therefore, is not expected to not 
result in any environmental impacts. Thus, this rulemaking is covered 
by Categorical Exclusion A5 under 10 CFR part 1021, subpart D, which 
applies to any rulemaking that interprets or amends an existing rule 
without changing the environmental effect of that rule. Accordingly, 
neither an environmental assessment nor an environmental impact 
statement is required.

E. Review Under Executive Order 13132

    Executive Order 13132, ``Federalism,'' 64 FR 43255 (August 10, 
1999) imposes certain requirements on agencies formulating and 
implementing policies or regulations that preempt State law or that 
have Federalism implications. The Executive Order requires agencies to 
examine the constitutional and statutory authority supporting any 
action that would limit the policymaking discretion of the States and 
to carefully assess the necessity for such actions. The Executive Order 
also requires agencies to have an accountable process to ensure 
meaningful and timely input by State and local officials in the 
development of regulatory policies that have Federalism implications. 
On March 14, 2000, DOE published a statement of policy describing the 
intergovernmental consultation process it will follow in the 
development of such regulations. 65 FR 13735. DOE has examined this 
final rule and has determined that it would not have a substantial 
direct effect on the States, on the relationship between the national 
government and the States, or on the distribution of power and 
responsibilities among the various levels of government. EPCA governs 
and prescribes Federal preemption of State regulations as to energy 
conservation for the products that are the subject of this final rule. 
States can petition DOE for exemption from such preemption to the 
extent, and based on criteria, set forth in EPCA. (42 U.S.C. 6297(d)) 
No further action is required by Executive Order 13132.

F. Review Under Executive Order 12988

    Regarding the review of existing regulations and the promulgation 
of new regulations, section 3(a) of Executive Order 12988, ``Civil 
Justice Reform,'' 61 FR 4729 (Feb. 7, 1996), imposes on Federal 
agencies the general duty to adhere to the following requirements: (1) 
Eliminate drafting errors and ambiguity; (2) write regulations to 
minimize litigation; (3) provide a clear legal standard for affected 
conduct rather than a general standard; and (4) promote simplification 
and burden reduction. Regarding the review required by section 3(a), 
section 3(b) of Executive Order 12988 specifically requires that 
Executive agencies make every reasonable effort to ensure that the 
regulation: (1) Clearly specifies the preemptive effect, if any; (2) 
clearly specifies any effect on existing Federal law or regulation; (3) 
provides a clear legal standard for affected conduct while promoting 
simplification and burden reduction; (4) specifies the retroactive 
effect, if any; (5) adequately defines key terms; and (6) addresses 
other important issues affecting clarity and general draftsmanship 
under any guidelines issued by the Attorney General. Section 3(c) of 
Executive Order 12988 requires Executive agencies to review regulations 
in light of applicable standards in sections 3(a) and 3(b) to determine 
whether they are met or it is unreasonable to meet one or more of them. 
DOE has completed the required review and determined that, to the 
extent permitted by law, the final rule meets the relevant standards of 
Executive Order 12988.

G. Review Under the Unfunded Mandates Reform Act of 1995

    Title II of the Unfunded Mandates Reform Act of 1995 (UMRA) 
requires each Federal agency to assess the effects of Federal 
regulatory actions on State, local, and Tribal governments and the 
private sector. Public Law 104-4, sec. 201 (codified at 2 U.S.C. 1531). 
For a regulatory action likely to result in a rule that may cause the 
expenditure by State, local, and Tribal governments, in the aggregate, 
or by the private sector of $100 million or more in any one year 
(adjusted annually for inflation), section 202 of UMRA requires a 
Federal agency

[[Page 96231]]

to publish a written statement that estimates the resulting costs, 
benefits, and other effects on the national economy. (2 U.S.C. 1532(a), 
(b)) The UMRA also requires a Federal agency to develop an effective 
process to permit timely input by elected officers of State, local, and 
Tribal governments on a proposed ``significant intergovernmental 
mandate,'' and requires an agency plan for giving notice and 
opportunity for timely input to potentially affected small governments 
before establishing any requirements that might significantly or 
uniquely affect them. On March 18, 1997, DOE published a statement of 
policy on its process for intergovernmental consultation under UMRA. 62 
FR 12820. (This policy is also available at http://energy.gov/gc/office-general-counsel.) DOE examined this final rule according to UMRA 
and its statement of policy and determined that the rule contains 
neither an intergovernmental mandate, nor a mandate that may result in 
the expenditure by State, local, and Tribal governments, in the 
aggregate, or by the private sector, of $100 million or more in any 
year. Accordingly, no further assessment or analysis is required under 
UMRA.

H. Review Under the Treasury and General Government Appropriations Act, 
1999

    Section 654 of the Treasury and General Government Appropriations 
Act, 1999 (Pub. L. 105-277) requires Federal agencies to issue a Family 
Policymaking Assessment for any rule that may affect family well-being. 
This rule would not have any impact on the autonomy or integrity of the 
family as an institution. Accordingly, DOE has concluded that it is not 
necessary to prepare a Family Policymaking Assessment.

I. Review Under Executive Order 12630

    Pursuant to Executive Order 12630, ``Governmental Actions and 
Interference with Constitutionally Protected Property Rights,'' 53 FR 
8859 (March 18, 1988), DOE has determined that this regulation would 
not result in any takings that might require compensation under the 
Fifth Amendment to the U.S. Constitution.

J. Review Under Treasury and General Government Appropriations Act, 
2001

    Section 515 of the Treasury and General Government Appropriations 
Act, 2001 (44 U.S.C. 3516 note) provides for agencies to review most 
disseminations of information to the public under information quality 
guidelines established by each agency pursuant to general guidelines 
issued by OMB. OMB's guidelines were published at 67 FR 8452 (Feb. 22, 
2002), and DOE's guidelines were published at 67 FR 62446 (Oct. 7, 
2002). DOE has reviewed this final rule under the OMB and DOE 
guidelines and has concluded that it is consistent with applicable 
policies in those guidelines.

K. Review Under Executive Order 13211

    Executive Order 13211, ``Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution, or Use,'' 66 FR 28355 
(May 22, 2001), requires Federal agencies to prepare and submit to OIRA 
at OMB, a Statement of Energy Effects for any significant energy 
action. A ``significant energy action'' is defined as any action by an 
agency that promulgates or is expected to lead to promulgation of a 
final rule, and that: (1) Is a significant regulatory action under 
Executive Order 12866, or any successor order; and (2) is likely to 
have a significant adverse effect on the supply, distribution, or use 
of energy; or (3) is designated by the Administrator of OIRA as a 
significant energy action. For any significant energy action, the 
agency must give a detailed statement of any adverse effects on energy 
supply, distribution, or use if the regulation is implemented, and of 
reasonable alternatives to the action and their expected benefits on 
energy supply, distribution, and use.
    This regulatory action, which develops conversion factors to amend 
the energy conservation standards for consumer and certain commercial 
water heaters in light of new test procedures is not a significant 
regulatory action under Executive Order 12866 or any successor order. 
Moreover, it will not have a significant adverse effect on the supply, 
distribution, or use of energy, nor has it been designated as a 
significant energy action by the Administrator of OIRA. Therefore, it 
is not a significant energy action, and, accordingly, DOE has not 
prepared a Statement of Energy Effects for this rulemaking.

L. Review Under Section 32 of the Federal Energy Administration Act of 
1974

    Under section 301 of the Department of Energy Organization Act 
(Pub. L. 95-91; 42 U.S.C. 7101 et seq.), DOE must comply with all laws 
applicable to the former Federal Energy Administration, including 
section 32 of the Federal Energy Administration Act of 1974 (Pub. L. 
93-275), as amended by the Federal Energy Administration Authorization 
Act of 1977 (Pub. L. 95-70). (15 U.S.C. 788; FEAA) Section 32 
essentially provides in relevant part that, where a proposed rule 
authorizes or requires use of commercial standards, the notice of 
proposed rulemaking must inform the public of the use and background of 
such standards. In addition, section 32(c) requires DOE to consult with 
the Attorney General and the Chairman of the Federal Trade Commission 
(FTC) concerning the impact of the commercial or industry standards on 
competition.
    This final rule to implement conversion factors between the 
existing water heaters test procedure and the amended test procedure 
does not incorporate testing methods contained in commercial standards.

M. Congressional Notification

    As required by 5 U.S.C. 801, DOE will report to Congress on the 
promulgation of this rule before its effective date. The report will 
state that it has been determined that the rule is not a ``major rule'' 
as defined by 5 U.S.C. 804(2).

V. Approval of the Office of the Secretary

    The Secretary of Energy has approved publication of this final 
rule.

List of Subjects

10 CFR Part 429

    Confidential business information, Energy conservation, Household 
appliances, Imports, Incorporation by reference, Reporting and 
recordkeeping requirements.

10 CFR Part 430

    Administrative practice and procedure, Confidential business 
information, Energy conservation, Household appliances, Imports, 
Incorporation by reference, Intergovernmental relations, Small 
businesses.

10 CFR Part 431

    Administrative practice and procedure, Confidential business 
information, Test procedures, Incorporation by reference, Reporting and 
recordkeeping requirements.

    Issued in Washington, DC, on December 6, 2016.
Kathleen B. Hogan,
Deputy Assistant Secretary for Energy Efficiency, Energy Efficiency and 
Renewable Energy.

    For the reasons stated in the preamble, DOE amends parts 429, 430, 
and 431 of chapter II subchapter D of title 10, Code of Federal 
Regulations as set forth below:

[[Page 96232]]

PART 429--CERTIFICATION, COMPLIANCE, AND ENFORCEMENT FOR CONSUMER 
PRODUCTS AND COMMERCIAL AND INDUSTRIAL EQUIPMENT

0
1. The authority citation for part 429 continues to read as follows:

    Authority: 42 U.S.C. 6291-6317; 28 U.S.C. 2461 note.

0
2. Section 429.17 is revised to read as follows:


Sec.  429.17  Water heaters.

    (a) Determination of represented value. (1) As of July 13, 2015, 
manufacturers must determine the represented value for each new basic 
model of water heater by applying an alternative efficiency 
determination method (AEDM) in accordance with 10 CFR 429.70 or by 
testing for the uniform energy factor, in conjunction with the 
applicable sampling provisions as follows:
    (i) If the represented value is determined through testing, the 
general requirements of 10 CFR 429.11 are applicable; and
    (ii) For each basic model selected for testing, a sample of 
sufficient size shall be randomly selected and tested to ensure that--
    (A) Any represented value of the energy consumption or other 
measure of energy use of a basic model for which consumers would favor 
lower values shall be greater than or equal to the higher of:
    (1) The mean of the sample, where:
    [GRAPHIC] [TIFF OMITTED] TR29DE16.005
    

and, x is the sample mean; n is the number of samples; and 
xi is the ith sample;


Or,

    (2) The upper 95-percent confidence limit (UCL) of the true mean 
divided by 1.10, where
[GRAPHIC] [TIFF OMITTED] TR29DE16.006

    And x is the sample mean; s is the sample standard deviation; n is 
the number of samples; and t0.95 is the t statistic for a 
95-percent one-tailed confidence interval with n-1 degrees of freedom 
(from Appendix A).
    (B) Any represented value of energy efficiency or other measure of 
energy consumption of a basic model for which consumers would favor 
higher values shall be less than or equal to the lower of:
    (1) The mean of the sample, where:
    [GRAPHIC] [TIFF OMITTED] TR29DE16.007
    

and, x is the sample mean; n is the number of samples; and 
xi is the ith sample;


Or,

    (2) The lower 95-percent confidence limit (LCL) of the true mean 
divided by 0.90, where:
[GRAPHIC] [TIFF OMITTED] TR29DE16.008

    And x is the sample mean; s is the sample standard deviation; n is 
the number of samples; and t0.95 is the t statistic for a 
95-percent one-tailed confidence interval with n-1 degrees of freedom 
(from Appendix A).
    (C) Any represented value of the rated storage volume must be equal 
to the mean of the measured storage volumes of all the units within the 
sample.
    (D) Any represented value of first-hour rating or maximum gallons 
per minute (GPM) must be equal to the mean of the measured first-hour 
ratings or measured maximum GPM ratings, respectively, of all the units 
within the sample.
    (2) For basic models initially certified before July 13, 2015 
(using either the energy factor test procedure contained in appendix E 
to subpart B of 10 CFR part 430 of the January 1, 2015 edition of the 
Code of Federal Regulations or the thermal efficiency and standby loss 
test procedures contained in 10 CFR 431.106 of the January 1, 2015 
edition of the Code of Federal Regulations, in conjunction with 
applicable sampling provisions), manufacturers must:
    (i) Determine the represented value for each basic model by 
applying an AEDM in accordance with 10 CFR 429.70 or by testing for the 
uniform energy factor, in conjunction with the applicable sampling 
provisions of paragraph (a)(1) of this section; or
    (ii) Calculate the uniform energy factor for each test sample by 
applying the following mathematical conversion factors to test data 
previously obtained through testing according to appendix E to subpart 
B of 10 CFR part 430 of the January 1, 2015 edition of the Code of 
Federal Regulations or the thermal efficiency and standby loss test 
procedures contained in 10 CFR 431.106 of the January 1, 2015, edition 
of the Code of Federal Regulations. Represented values of uniform 
energy factor, first-hour rating, and maximum GPM rating based on a 
calculation using this mathematical conversion factor must be 
determined using the applicable sampling provisions in paragraphs 
(a)(1)(i) and (ii) of this section.
    (A) Calculate the New First Hour Rating (New FHR) or New Max 
Gallons per Minute (New Max GPM), as applicable, using the equations 
presented in the table in this paragraph.

------------------------------------------------------------------------
                                  Distinguishing
         Product class               criteria       Conversion factor *
------------------------------------------------------------------------
Consumer Gas-fired Water        Non-Condensing,    New FHR = 7.9592 +
 Heater.                         Standard and Low   0.8752 x FHRP.
                                 NOX.
                                Non-Condensing,    New FHR = 25.0680 +
                                 Ultra-Low NOX.     0.6535 x FHRP.
                                Condensing.......  New FHR = 1.0570 x
                                                    FHRP.
Consumer Oil-fired Water        N/A..............  New FHR = 0.9102 x
 Heater.                                            FHRP.
Consumer Electric Water Heater  Electric           New FHR = 9.2827 +
                                 Resistance.        0.8092 x FHRP.
                                Heat Pump........  New FHR = -4.2705 +
                                                    0.9947 x FHRP.
Tabletop Water Heater.........  N/A..............  New FHR = 41.5127 +
                                                    0.1989 x FHRP.
Instantaneous Gas-fired Water   N/A..............  New Max GPM = 1.1461
 Heater.                                            x Max GPMP.
Instantaneous Electric Water    N/A..............  New Max GPM = 1.1461
 Heater.                                            x Max GPMP.
Grid-Enabled Water Heater.....  N/A..............  New FHR = 9.2827 +
                                                    0.8092 x FHRP.
Residential-Duty Commercial     N/A..............  New FHR = -35.8233 +
 Gas-fired Water Heater.                            0.4649 x Vm +
                                                    160.5089 x Et.
Residential-Duty Commercial     N/A..............  New FHR = -35.8233 +
 Oil-fired Water Heater.                            0.4649 x Vm +
                                                    160.5089 x Et.

[[Page 96233]]

 
Residential-Duty Commercial     N/A..............  New Max GPM = 0.0146
 Electric Instantaneous Water                       + 0.0295 x Q.
 Heater.
------------------------------------------------------------------------
FHRP = prior first-hour rating.
Max GPMP = prior maximum GPM rating.
Q = nameplate input rate, in kBtu/h.
Et = thermal efficiency rating.
Vm = measured storage volume in gallons.

    (B) Determine the applicable draw pattern as follows:
    (1) For consumer gas-fired water heaters, consumer oil-fired water 
heaters, consumer electric water heaters, tabletop water heaters, grid-
enabled water heaters, residential-duty commercial gas water heaters, 
residential-duty commercial oil-fired water heaters: Use the New FHR 
(as defined in paragraph (a)(2)(ii)(A) of this section) to select the 
applicable draw pattern from the table in this paragraph:

------------------------------------------------------------------------
  New FHR greater than or equal    and new FHR less
               to:                       than:           Draw pattern
------------------------------------------------------------------------
0 gallons.......................  18 gallons........  Very Small.
18 gallons......................  51 gallons........  Low.
51 gallons......................  75 gallons........  Medium.
75 gallons......................  No upper limit....  High.
------------------------------------------------------------------------

    (2) For instantaneous gas-fired water heaters, instantaneous 
electric water heaters, and residential-duty commercial electric 
instantaneous water heaters: Use New Max GPM (as defined in paragraph 
(a)(2)(ii)(A) of this section) to select the applicable draw pattern 
from the table in this paragraph:

------------------------------------------------------------------------
   New max GPM greater than or      And new max GPM
            equal to:              rating less than:     Draw pattern
------------------------------------------------------------------------
0 gallons/minute................  1.7 gallons/minute  Very Small.
1.7 gallons/minute..............  2.8 gallons/minute  Low.
2.8 gallons/minute..............  4 gallons/minute..  Medium.
4 gallons/minute................  No upper limit....  High.
------------------------------------------------------------------------

    (C) For consumer electric heat pump water heaters, use the draw 
pattern to determine the applicable drawn volume (DV) from the table in 
this paragraph:

------------------------------------------------------------------------
               Draw pattern                              DV
------------------------------------------------------------------------
Very Small................................  10 gallons.
Low.......................................  38 gallons.
Medium....................................  55 gallons.
High......................................  84 gallons.
------------------------------------------------------------------------

    (D) For each class besides consumer electric heat pump water 
heaters, use the applicable equation to calculate: UEFWHAM 
(for consumer storage water heaters-except heat pumps), 
UEFmodel (for consumer instantaneous water heaters), 
UEFrd (for residential-duty commercial storage water 
heaters), and UEFrd, model (for residential-duty commercial 
electric instantaneous water heaters) as follows:
    (1) For consumer storage water heaters (except consumer electric 
heat pump water heaters):
[GRAPHIC] [TIFF OMITTED] TR29DE16.009

    Where a, b, c, and d are coefficients based on the applicable draw 
pattern as specified in the table below; EF is the energy factor; 
[eta]r is the recovery efficiency in decimal form; and P is 
the input rate in Btu/h.

----------------------------------------------------------------------------------------------------------------
                  Draw pattern                           a               b               c               d
----------------------------------------------------------------------------------------------------------------
Very Small......................................        0.250266            57.5        0.039864            67.5
Low.............................................        0.065860            57.5        0.039864            67.5
Medium..........................................        0.045503            57.5        0.039864            67.5
High............................................        0.029794            57.5        0.039864            67.5
----------------------------------------------------------------------------------------------------------------

    (2) For consumer instantaneous water heaters:

[[Page 96234]]

[GRAPHIC] [TIFF OMITTED] TR29DE16.010

    Where [eta]r is the recovery efficiency expressed in 
decimal form and A is dependent upon the applicable draw pattern and 
fuel type as specified in the table in this paragraph.

------------------------------------------------------------------------
                                                         A
              Draw pattern               -------------------------------
                                             Electric           Gas
------------------------------------------------------------------------
Very Small..............................        0.003819        0.026915
Low.....................................        0.001549        0.010917
Medium..................................        0.001186        0.008362
High....................................        0.000785        0.005534
------------------------------------------------------------------------

    (3) For residential-duty commercial storage water heaters:
    [GRAPHIC] [TIFF OMITTED] TR29DE16.011
    
    Where P is the input rate in Btu/h; Et is the thermal 
efficiency; SL is the standby loss in Btu/h; and F and G are 
coefficients as specified in the table in this paragraph based on the 
applicable draw pattern.

------------------------------------------------------------------------
              Draw pattern                       F               G
------------------------------------------------------------------------
Very Small..............................        0.821429       0.0043520
Low.....................................        0.821429       0.0011450
Medium..................................        0.821429       0.0007914
High....................................        0.821429       0.0005181
------------------------------------------------------------------------

    (4) For residential-duty commercial electric instantaneous water 
heaters:
[GRAPHIC] [TIFF OMITTED] TR29DE16.012

    Where Et is the thermal efficiency expressed in decimal 
form and A is dependent upon the applicable draw pattern, as specified 
in the table in this paragraph.

------------------------------------------------------------------------
                      Draw pattern                               A
------------------------------------------------------------------------
Very Small..............................................        0.003819
Low.....................................................        0.001549
Medium..................................................        0.001186
High....................................................        0.000785
------------------------------------------------------------------------

    (E) Calculate the ``New UEF'' (i.e., the converted UEF) using the 
applicable equation in the table in this paragraph.

------------------------------------------------------------------------
                                 Distinguishing
        Product class               criteria          Conversion factor
------------------------------------------------------------------------
Consumer Gas-fired Water      Non-Condensing,       New UEF = -0.0002 +
 Heater.                       Standard and Low      0.9858 x UEFWHAM.
                               NOX.
                              Non-Condensing,       New UEF = 0.0746 +
                               Ultra-Low NOX.        0.8653 x UEFWHAM.
                              Condensing..........  New UEF = 0.4242 +
                                                     0.4641 x UEFWHAM.
Consumer Oil-fired Water      N/A.................  New UEF = -0.0033 +
 Heater.                                             0.9528 x UEFWHAM.
Consumer Electric Water       Electric Resistance.  New UEF = 0.4774 +
 Heater.                                             0.4740 x UEFWHAM.
                              Heat Pump...........  New UEF = 0.1513 +
                                                     0.8407 x EF +
                                                     0.0043 x DV.
Tabletop Water Heater.......  N/A.................  New UEF = -0.3305 +
                                                     1.3983 x UEFWHAM.
Instantaneous Gas-fired       N/A.................  New UEF = 0.1006 +
 Water Heater.                                       0.8622 x UEFmodel.
Instantaneous Electric Water  N/A.................  New UEF = 0.9847 x
 Heater.                                             UEFmodel.
Grid-Enabled Water Heater...  N/A.................  New UEF = 0.4774 +
                                                     0.4740 x UEFWHAM.
Residential-Duty Commercial   N/A.................  New UEF = -0.0022 +
 Gas-fired Water Heater.                             1.0002 x UEFrd.
Residential-Duty Commercial   N/A.................  New UEF = -0.0022 +
 Oil-fired Water Heater.                             1.0002 x UEFrd.

[[Page 96235]]

 
Residential-Duty Commercial   N/A.................  New UEF = UEFrd,
 Electric Instantaneous                              model.
 Water Heater.
------------------------------------------------------------------------
New UEF = converted UEF.
EF = Energy Factor.

    (b) Certification reports. (1) The requirements of 10 CFR 429.12 
apply; and
    (2) Pursuant to 10 CFR 429.12(b)(13), a certification report must 
include the following public, product-specific information:
    (i) For storage-type water heater basic models previously certified 
for energy factor pursuant to Sec.  429.17(a) of the January 1, 2015 
edition of the Code of Federal Regulations, and for which uniform 
energy factor is calculated pursuant to 10 CFR 429.17(a)(2)(ii): The 
energy factor (EF, rounded to the nearest 0.01), the uniform energy 
factor (UEF, rounded to the nearest 0.01), the rated storage volume in 
gallons (gal, rounded to the nearest 1 gal), the uniform energy factor 
test procedure first-hour rating in gallons (gal, rounded to the 
nearest 1 gal) as determined under paragraph (a)(2)(ii)(A) of this 
section, the previously certified first-hour rating under the energy 
factor test procedure in gallons (gal, rounded to the nearest 1 gal), 
and the recovery efficiency in percent (%, rounded to the nearest 1%);
    (ii) For storage-type water heater basic models rated pursuant to 
10 CFR 429.17(a)(1) or 10 CFR 429.17(a)(2)(i): The uniform energy 
factor (UEF, rounded to the nearest 0.01), the rated storage volume in 
gallons (gal, rounded to the nearest 1 gal), the first-hour rating in 
gallons (gal, rounded to the nearest 1 gal), and the recovery 
efficiency in percent (%, rounded to the nearest 1%);
    (iii) For instantaneous-type water heater basic models previously 
certified for energy factor pursuant to Sec.  429.17(a) of the January 
1, 2015 edition of the Code of Federal Regulations, and for which 
uniform energy factor is calculated pursuant to 10 CFR 
429.17(a)(2)(ii): The energy factor (EF, rounded to the nearest 0.01), 
the uniform energy factor (UEF. rounded to the nearest 0.01), the rated 
storage volume in gallons (gal, rounded to the nearest 1 gal), the 
uniform energy factor test procedure maximum gallons per minute (gpm, 
rounded to the nearest 0.1 gpm) as determined under paragraph 
(a)(2)(ii)(A) of this section, the previously certified maximum gallons 
per minute (gpm, rounded to the nearest 0.1 gpm) under the energy 
factor test procedure, and the recovery efficiency in percent (%, 
rounded to the nearest 1%);
    (iv) For instantaneous-type water heater basic models rated 
pursuant to 10 CFR 429.17(a)(1) or 10 CFR 429.17(a)(2)(i): The uniform 
energy factor (UEF, rounded to the nearest 0.01), the rated storage 
volume in gallons (gal, rounded to the nearest 1 gal), the maximum 
gallons per minute (gpm, rounded to the nearest 0.1 gpm), and the 
recovery efficiency in percent (%, rounded to the nearest 1%);
    (v) For grid-enabled water heater basic models previously certified 
for energy factor pursuant to 10 CFR 429.17(a) of the January 1, 2015 
edition of the Code of Federal Regulations, and for which uniform 
energy factor is calculated pursuant to 10 CFR 429.17(a)(2)(ii): The 
energy factor (EF, rounded to the nearest 0.01), the uniform energy 
factor (UEF, rounded to the nearest 0.01), the rated storage volume in 
gallons (gal, rounded to the nearest 1 gal), the uniform energy factor 
test procedure first-hour rating in gallons (gal, rounded to the 
nearest 1 gal) as determined under paragraph (a)(2)(ii)(A) of this 
section, the previously certified first-hour rating under the energy 
factor test procedure in gallons (gal, rounded to the nearest 1 gal), 
the recovery efficiency in percent (%, rounded to the nearest 1%), a 
declaration that the model is a grid-enabled water heater, whether it 
is equipped at the point of manufacture with an activation lock, and 
whether it bears a permanent label applied by the manufacturer that 
advises purchasers and end-users of the intended and appropriate use of 
the product; and
    (vi) For grid-enabled water heater basic models rated pursuant to 
10 CFR 429.17(a)(1) or 10 CFR 429.17(a)(2)(i): The uniform energy 
factor (UEF, rounded to the nearest 0.01), the rated storage volume in 
gallons (gal, rounded to the nearest 1 gal), the first-hour rating in 
gallons (gal, rounded to the nearest 1 gal), and the recovery 
efficiency in percent (%, rounded to the nearest 1%), a declaration 
that the model is a grid-enabled water heater, whether it is equipped 
at the point of manufacture with an activation lock, and whether it 
bears a permanent label applied by the manufacturer that advises 
purchasers and end-users of the intended and appropriate use of the 
product.

0
3. Section 429.17 is further revised, effective December 29, 2017, to 
read as follows:


Sec.  429.17  Water heaters.

    (a) Determination of represented value. (1) Manufacturers must 
determine the represented value for each water heater by applying an 
AEDM in accordance with 10 CFR 429.70 or by testing for the uniform 
energy factor, in conjunction with the applicable sampling provisions 
as follows:
    (i) If the represented value is determined through testing, the 
general requirements of 10 CFR 429.11 are applicable; and
    (ii) For each basic model selected for testing, a sample of 
sufficient size shall be randomly selected and tested to ensure that--
    (A) Any represented value of the estimated annual operating cost or 
other measure of energy consumption of a basic model for which 
consumers would favor lower values shall be greater than or equal to 
the higher of:
    (1) The mean of the sample, where:
    [GRAPHIC] [TIFF OMITTED] TR29DE16.013
    

and, x is the sample mean; n is the number of samples; and 
xi is the ith sample;


Or,

    (2) The upper 95-percent confidence limit (UCL) of the true mean 
divided by 1.10, where:
[GRAPHIC] [TIFF OMITTED] TR29DE16.014

    And x is the sample mean; s is the sample standard deviation; n is 
the number of samples; and t0.95 is the t statistic for a 
95-percent one-tailed confidence interval with n-1 degrees of freedom 
(from Appendix A).
    (B) Any represented value of the uniform energy factor, or other 
measure of energy consumption of a basic model for which consumers 
would favor higher values shall be less than or equal to the lower of:
    (1) The mean of the sample, where:
    [GRAPHIC] [TIFF OMITTED] TR29DE16.015
    

[[Page 96236]]



and, x is the sample mean; n is the number of samples; and 
xi is the ith sample;


Or,

    (2) The lower 95-percent confidence limit (LCL) of the true mean 
divided by 0.90, where:
[GRAPHIC] [TIFF OMITTED] TR29DE16.016

    And x is the sample mean; s is the sample standard deviation; n is 
the number of samples; and t0.95 is the t statistic for a 
95-percent one-tailed confidence interval with n-1 degrees of freedom 
(from Appendix A).
    (C) Any represented value of the rated storage volume must be equal 
to the mean of the measured storage volumes of all the units within the 
sample.
    (D) Any represented value of first-hour rating or maximum gallons 
per minute (GPM) must be equal to the mean of the measured first-hour 
ratings or measured maximum GPM ratings, respectively, of all the units 
within the sample.
    (b) Certification reports. (1) The requirements of 10 CFR 429.12 
are applicable to water heaters; and
    (2) Pursuant to 10 CFR 429.12(b)(13), a certification report shall 
include the following public, product-specific information:
    (i) For storage-type water heater basic models: The uniform energy 
factor (UEF, rounded to the nearest 0.01), the rated storage volume in 
gallons (rounded to the nearest 1 gal), the first-hour rating in 
gallons (gal, rounded to the nearest 1 gal), and the recovery 
efficiency in percent (%, rounded to the nearest 1%);
    (ii) For instantaneous-type water heater basic models: The uniform 
energy factor (UEF, rounded to the nearest 0.01), the rated storage 
volume in gallons (gal, rounded to the nearest 1 gal), the maximum 
gallons per minute (gpm, rounded to the nearest 0.1 gpm), and the 
recovery efficiency in percent (%, rounded to the nearest 1%); and
    (iii) For grid-enabled water heater basic models: The uniform 
energy factor (UEF, rounded to the nearest 0.01), the rated storage 
volume in gallons (gal, rounded to the nearest 1 gal), the first-hour 
rating in gallons (gal, rounded to the nearest 1 gal), the recovery 
efficiency in percent (%, rounded to the nearest 1%), a declaration 
that the model is a grid-enabled water heater, whether it is equipped 
at the point of manufacture with an activation lock, and whether it 
bears a permanent label applied by the manufacturer that advises 
purchasers and end-users of the intended and appropriate use of the 
product.

0
4. Section 429.44 is amended by adding paragraph (d) to read as 
follows:


Sec.  429.44  Commercial water heating equipment.

* * * * *
    (d) Certification reports for residential-duty commercial water 
heaters. (1) The requirements of Sec.  429.12 apply; and
    (2) Pursuant to Sec.  429.12(b)(13), a certification report must 
include the following public, equipment-specific information:
    (i) Residential-duty commercial gas-fired and oil-fired storage 
water heaters previously certified for thermal efficiency and standby 
loss pursuant to 10 CFR 429.44(b) of the January 1, 2015 edition of the 
Code of Federal Regulations, and for which uniform energy factor is 
calculated pursuant to 10 CFR 429.17(a)(2)(ii): The thermal efficiency 
in percent (%), the standby loss in British thermal units per hour 
(Btu/h), the uniform energy factor (UEF, rounded to the nearest 0.01), 
the rated storage volume in gallons (gal), and the nameplate input rate 
in Btu/h.
    (ii) Residential-duty commercial gas-fired and oil-fired storage 
water heaters rated for uniform energy factor pursuant to 10 CFR 
429.17(a)(2)(i): The uniform energy factor (UEF, rounded to the nearest 
0.01), the rated storage volume in gallons (rounded to the nearest 1 
gal), the first-hour rating in gallons (gal, rounded to the nearest 1 
gal), and the recovery efficiency in percent (%, rounded to the nearest 
1%).
    (iii) Residential-duty commercial electric instantaneous water 
heaters previously certified for thermal efficiency and standby loss 
pursuant to 10 CFR 429.44(b) of the January 1, 2015 edition of the Code 
of Federal Regulations, and for which uniform energy factor is 
calculated pursuant to 10 CFR 429.17(a)(2)(ii): The thermal efficiency 
in percent (%), the standby loss in British thermal units per hour 
(Btu/h), the uniform energy factor (UEF, rounded to the nearest 0.01), 
the rated storage volume in gallons (gal), and the nameplate input rate 
in kilowatts (kW).
    (iv) Residential-duty commercial electric instantaneous water 
heaters rated for uniform energy factor pursuant to 10 CFR 
429.17(a)(2)(i): The uniform energy factor (UEF, rounded to the nearest 
0.01), the rated storage volume in gallons (gal, rounded to the nearest 
1 gal), the maximum gallons per minute (gpm, rounded to the nearest 0.1 
gpm), and the recovery efficiency in percent (%, rounded to the nearest 
1%)).
* * * * *

0
5. Section 429.44 is further revised, effective December 29, 2017, by 
revising paragraph (d)(2) to read as follows:


Sec.  429.44  Commercial water heating equipment.

* * * * *
    (d) * * *
    (2) Pursuant to Sec.  429.12(b)(13), a certification report for 
equipment must include the following public, equipment-specific 
information:
    (i) Residential-duty commercial gas-fired and oil-fired storage 
water heaters: The uniform energy factor (UEF, rounded to the nearest 
0.01), the rated storage volume in gallons (gal, rounded to the nearest 
1 gal), the first-hour rating in gallons (gal, rounded to the nearest 1 
gal), and the recovery efficiency in percent (%, rounded to the nearest 
1%).
    (ii) Residential-duty commercial electric instantaneous water 
heaters: The uniform energy factor (UEF, rounded to the nearest 0.01), 
the rated storage volume in gallons (gal, rounded to the nearest 1 
gal), the maximum gallons per minute (gpm, rounded to the nearest 0.1 
gpm), and the recovery efficiency in percent (%, rounded to the nearest 
1%).
* * * * *

0
6. Section 429.134 is amended by revising paragraph (d)(2) to read as 
follows:


Sec.  429.134   Product-specific enforcement provisions.

* * * * *
    (d) * * *
    (2) Verification of rated storage volume. The storage volume of the 
basic model will be measured pursuant to the test requirements of 
appendix E to subpart B of 10 CFR part 430 for each unit tested. The 
mean of the measured values will be compared to the rated storage 
volume as certified by the manufacturer. The rated value will be 
considered valid only if the measurement is within 3 percent of the 
certified rating.
    (i) If the rated storage volume is found to be within 3 percent of 
the mean of the measured value of storage volume, then the rated value 
will be used as the basis for calculation of the required uniform 
energy factor for the basic model.
    (ii) If the rated storage volume is found to vary more than 3 
percent from the mean of the measured values, then the mean of the 
measured values will be used as the basis for calculation of the 
required uniform energy factor for the basic model.
* * * * *

[[Page 96237]]

PART 430--ENERGY CONSERVATION PROGRAM FOR CONSUMER PRODUCTS

0
7. The authority citation for part 430 continues to read as follows:

    Authority:  42 U.S.C. 6291-6309; 28 U.S.C. 2461 note.


0
8. Section 430.23 is amended by revising paragraph (e) to read as 
follows:


Sec.  430.23  Test procedures for the measurement of energy and water 
consumption.

* * * * *
    (e) Water heaters. (1) For water heaters tested using energy factor 
and for which uniform energy factor is determined using the conversion 
factors in accordance with 10 CFR 429.17(a)(2):
    (i) The estimated annual operating cost is calculated as--
    (A) For a gas-fired or oil-fired water heater, the product of the 
annual energy consumption, determined according to section 6.3.7 or 
6.4.4 of appendix E of this subpart, times the representative average 
unit cost of gas or oil, as appropriate, in dollars per Btu as provided 
by the Secretary. Round the resulting product to the nearest dollar per 
year.
    (B) For an electric water heater, the product of the annual energy 
consumption, determined according to section 6.3.7 or 6.4.4 of appendix 
E of this subpart, times the representative average unit cost of 
electricity in dollars per kilowatt-hour as provided by the Secretary, 
divided by 3412 Btu per kilowatt-hour. Round the resulting product to 
the nearest dollar per year.
    (ii) For an individual unit, determine the tested energy factor in 
accordance with section 6.1.7 or 6.2.4 of appendix E to subpart B of 10 
CFR part 430 of the January 1, 2015 edition of the Code of Federal 
Regulations, and round the value to the nearest 0.01. Determine the 
converted uniform energy factor in accordance with 10 CFR 429.17(a)(2), 
and round the value to the nearest 0.01.
    (2) For water heaters tested using uniform energy factor:
    (i) The estimated annual operating cost is calculated as:
    (A) For a gas-fired or oil-fired water heater, the sum of: The 
product of the annual gas or oil energy consumption, determined 
according to section 6.3.9 or 6.4.6 of appendix E of this subpart, 
times the representative average unit cost of gas or oil, as 
appropriate, in dollars per Btu as provided by the Secretary; plus the 
product of the annual electric energy consumption, determined according 
to section 6.3.8 or 6.4.5 of appendix E of this subpart, times the 
representative average unit cost of electricity in dollars per 
kilowatt-hour as provided by the Secretary. Round the resulting sum to 
the nearest dollar per year.
    (B) For an electric water heater, the product of the annual energy 
consumption, determined according to section 6.3.7 or 6.4.4 of appendix 
E of this subpart, times the representative average unit cost of 
electricity in dollars per kilowatt-hour as provided by the Secretary. 
Round the resulting product to the nearest dollar per year.
    (ii) For an individual unit, determine the tested uniform energy 
factor in accordance with section 6.3.6 or 6.4.3 of appendix E of this 
subpart, and round the value to the nearest 0.01.
* * * * *

0
9. Section 430.23 paragraph (e) is further revised, effective December 
29, 2017, to read as follows:


Sec.  430.23  Test procedures for the measurement of energy and water 
consumption.

* * * * *
    (e) Water heaters. (1) The estimated annual operating cost is 
calculated as:
    (i) For a gas-fired or oil-fired water heater, the sum of: The 
product of the annual gas or oil energy consumption, determined 
according to section 6.3.9 or 6.4.6 of appendix E of this subpart, 
times the representative average unit cost of gas or oil, as 
appropriate, in dollars per Btu as provided by the Secretary; plus the 
product of the annual electric energy consumption, determined according 
to section 6.3.8 or 6.4.5 of appendix E of this subpart, times the 
representative average unit cost of electricity in dollars per 
kilowatt-hour as provided by the Secretary. Round the resulting sum to 
the nearest dollar per year.
    (ii) For an electric water heater, the product of the annual energy 
consumption, determined according to section 6.3.7 or 6.4.4 of appendix 
E of this subpart, times the representative average unit cost of 
electricity in dollars per kilowatt-hour as provided by the Secretary. 
Round the resulting product to the nearest dollar per year.
    (2) For an individual unit, determine the tested uniform energy 
factor in accordance with section 6.3.6 or 6.4.3 of appendix E of this 
subpart, and round the value to the nearest 0.01.
* * * * *

0
10. Section 430.32 is amended by revising paragraph (d) to read as 
follows:


Sec.  430.32   Energy and water conservation standards and their 
compliance dates.

* * * * *
    (d) Water heaters. The uniform energy factor of water heaters shall 
not be less than the following:

----------------------------------------------------------------------------------------------------------------
                                     Rated storage
                                    volume and input
          Product class                rating (if          Draw pattern             Uniform energy factor
                                      applicable)
----------------------------------------------------------------------------------------------------------------
Gas-fired Storage Water Heater..  >=20 gal and <=55    Very Small.........  0.3456 - (0.0020 x Vr)
                                   gal.
                                                       Low................  0.5982 - (0.0019 x Vr)
                                                       Medium.............  0.6483 - (0.0017 x Vr)
                                                       High...............  0.6920 - (0.0013 x Vr)
                                  >55 gal and <=100    Very Small.........  0.6470 - (0.0006 x Vr)
                                   gal.
                                                       Low................  0.7689 - (0.0005 x Vr)
                                                       Medium.............  0.7897 - (0.0004 x Vr)
                                                       High...............  0.8072 - (0.0003 x Vr)
Oil-fired Storage Water Heater..  <=50 gal...........  Very Small.........  0.2509 - (0.0012 x Vr)
                                                       Low................  0.5330 - (0.0016 x Vr)
                                                       Medium.............  0.6078 - (0.0016 x Vr)
                                                       High...............  0.6815 - (0.0014 x Vr)
Electric Storage Water Heaters..  >=20 gal and <=55    Very Small.........  0.8808 - (0.0008 x Vr)
                                   gal.
                                                       Low................  0.9254 - (0.0003 x Vr)
                                                       Medium.............  0.9307 - (0.0002 x Vr)
                                                       High...............  0.9349 - (0.0001 x Vr)
                                  >55 gal and <=120    Very Small.........  1.9236 - (0.0011 x Vr)
                                   gal.
                                                       Low................  2.0440 - (0.0011 x Vr)

[[Page 96238]]

 
                                                       Medium.............  2.1171 - (0.0011 x Vr)
                                                       High...............  2.2418 - (0.0011 x Vr)
Tabletop Water Heater...........  >=20 gal and <=120   Very Small.........  0.6323 - (0.0058 x Vr)
                                   gal.
                                                       Low................  0.9188 - (0.0031 x Vr)
                                                       Medium.............  0.9577 - (0.0023 x Vr)
                                                       High...............  0.9884 - (0.0016 x Vr)
Instantaneous Gas-fired Water     <2 gal and >50,000   Very Small.........  0.80
 Heater.                           Btu/h.              Low................  0.81
                                                       Medium.............  0.81
                                                       High...............  0.81
Instantaneous Electric Water      <2 gal.............  Very Small.........  0.91
 Heater.
                                                       Low................  0.91
                                                       Medium.............  0.91
                                                       High...............  0.92
Grid-Enabled Water Heater.......  >75 gal............  Very Small.........  1.0136 - (0.0028 x Vr)
                                                       Low................  0.9984 - (0.0014 x Vr)
                                                       Medium.............  0.9853 - (0.0010 x Vr)
                                                       High...............  0.9720 - (0.0007 x Vr)
----------------------------------------------------------------------------------------------------------------
* Vr is the Rated Storage Volume (in gallons), as determined pursuant to 10 CFR 429.17.

* * * * *

PART 431--ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND 
INDUSTRIAL EQUIPMENT

0
11. The authority citation for part 431 continues to read as follows:

    Authority:  42 U.S.C. 6291-6317; 28 U.S.C. 2461 note.


0
12. Section 431.110 is revised to read as follows:


Sec.  431.110  Energy conservation standards and their effective dates.

    (a) Each commercial storage water heater, instantaneous water 
heater, unfired hot water storage tank and hot water supply boiler 
(excluding residential-duty commercial water heaters) must meet the 
applicable energy conservation standard level(s) as specified in the 
table in this paragraph. Any packaged boiler that provides service 
water that meets the definition of ``commercial packaged boiler'' in 
subpart E of this part, but does not meet the definition of ``hot water 
supply boiler'' in subpart G, must meet the requirements that apply to 
it under subpart E.

----------------------------------------------------------------------------------------------------------------
                                                                        Energy conservation standard \a\
                                                              --------------------------------------------------
                                                                                      Minimum
                                                                                      thermal
                                                                                    efficiency        Minimum
                                                                Maximum standby     (equipment        thermal
       Equipment category                    Size                   loss \c\       manufactured     efficiency
                                                                   (equipment      on and after     (equipment
                                                                manufactured on     October 29,    manufactured
                                                               and after October     2003 and      on and after
                                                                 29, 2003) \b\    before October    October 9,
                                                                                   9, 2015) \b\    2015) \b\ (%)
                                                                                        (%)
----------------------------------------------------------------------------------------------------------------
Electric storage water heaters.  All.........................  0.30 + 27/Vm (%/              N/A             N/A
                                                                hr).
Gas-fired storage water heaters  <=155,000 Btu/hr............  Q/800 + 110(Vr)\1/             80              80
                                                                2\ (Btu/hr).
                                 >155,000 Btu/hr.............  Q/800 + 110(Vr)\1/             80              80
                                                                2\ (Btu/hr).
Oil-fired storage water heaters  <=155,000 Btu/hr............  Q/800 + 110(Vr)\1/             78              80
                                                                2\ (Btu/hr).
                                 >155,000 Btu/hr.............  Q/800 + 110(Vr)\1/             78              80
                                                                2\ (Btu/hr).
Gas-fired instantaneous water    <10 gal.....................  N/A..............              80              80
 heaters and hot water supply    >=10 gal....................  Q/800 + 110(Vr)\1/             80              80
 boilers.                                                       2\ (Btu/hr).
Oil-fired instantaneous water    <10 gal.....................  N/A..............              80              80
 heaters and hot water supply    >=10 gal....................  Q/800 + 110(Vr)\1/             78              78
 boilers.                                                       2\ (Btu/hr).
----------------------------------------------------------------------------------------------------------------
                      Equipment category
                                                                      Size          Minimum thermal insulation
----------------------------------------------------------------------------------------------------------------
                Unfired hot water storage tank                 All..............              R-12.5
----------------------------------------------------------------------------------------------------------------
\a\ Vm is the measured storage volume (in gallons), and Vr is the rated volume (in gallons). Q is the nameplate
  input rate in Btu/hr.
\b\ For hot water supply boilers with a capacity of less than 10 gallons: (1) The standards are mandatory for
  products manufactured on and after October 21, 2005, and (2) products manufactured prior to that date, and on
  or after October 23, 2003, must meet either the standards listed in this table or the applicable standards in
  subpart E of this part for a ``commercial packaged boiler.''
\c\ Water heaters and hot water supply boilers having more than 140 gallons of storage capacity need not meet
  the standby loss requirement if: (1) The tank surface area is thermally insulated to R-12.5 or more; (2) a
  standing pilot light is not used; and (3) for gas or oil-fired storage water heaters, they have a fire damper
  or fan-assisted combustion.

    (b) Each residential-duty commercial water heater must meet the 
applicable energy conservation standard level(s) as follows:

[[Page 96239]]



----------------------------------------------------------------------------------------------------------------
          Product class            Specifications \a\      Draw pattern           Uniform energy factor \b\
----------------------------------------------------------------------------------------------------------------
Gas-fired Storage...............  >75 kBtu/hr and      Very Small.........  0.2674 - (0.0009 x Vr)
                                   <=105 kBtu/hr and   Low................  0.5362 - (0.0012 x Vr)
                                   <=120 gal.
                                                       Medium.............  0.6002 - (0.0011 x Vr)
                                                       High...............  0.6597 - (0.0009 x Vr)
Oil-fired Storage...............  >105 kBtu/hr and     Very Small.........  0.2932 - (0.0015 x Vr)
                                   <=140 kBtu/hr and   Low................  0.5596 - (0.0018 x Vr)
                                   <=120 gal.
                                                       Medium.............  0.6194 - (0.0016 x Vr)
                                                       High...............  0.6740 - (0.0013 x Vr)
Electric Instantaneous..........  >12 kW and <=58.6    Very Small.........  0.80
                                   kW and <=2 gal.
                                                       Low................  0.80
                                                       Medium.............  0.80
                                                       High...............  0.80
----------------------------------------------------------------------------------------------------------------
\a\ Additionally, to be classified as a residential-duty commercial water heater, a commercial water heater must
  meet the following conditions: (1) if the water heater requires electricity, it must use a single-phase
  external power supply; and (2) the water heater must not be designed to heat water to temperatures greater
  than 180 [deg]F.
\b\ Vr is the rated storage volume (in gallons), as determined pursuant to 10 CFR 429.44.

[FR Doc. 2016-29994 Filed 12-28-16; 8:45 am]
 BILLING CODE 6450-01-P